Methods and apparatus for displaying and processing facilities map information and/or other image information on a marking device

ABSTRACT

A marking device for a marking operation to mark a presence of an absence of one or more underground facilities is configured to access and display facilities map information, and/or other image information, as a visual aid to facilitate the marking operation. In various aspects, methods and apparatus relate to: selection of an “base” facilities map, or information from a database of facilities map data, relating to a given work side/dig area; selection of an pan and/or zoom (resolution) for displaying facilities map information; updating displayed facilities map information while a marking device is used during a marking operation (e.g. changing pan, zoom and/or orientation); overlaying on the displayed facilities map information marking information and/or landmark information relating to the marking operation; and storing locally on the marking device, and/or transmitting from the marking device, facilities map information and/or overlaid marking/landmark information (e.g., for further processing, analysis and/or subsequent display).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims a priority benefit, under 35 U.S.C. §120, as acontinuation (CON) of U.S. Non-provisional application Ser. No.12/701,496, entitled, “Methods And Apparatus For Displaying AndProcessing Facilities Map Information And/Or Other Image Information OnA Marking Device,” filed on Feb. 5, 2010 under attorney docket no.DYC0015US01.

application Ser. No. 12/701,496 claims a priority benefit, under 35U.S.C. §119(e), of U.S. Provisional Patent Application No. 61/151,562,entitled “Marking Device that has a Mechanism for Viewing FacilitiesMaps Integrated Therein and Associated Methods,” filed on Feb. 11, 2009under attorney docket no. DYC0015US00.

application Ser. No. 12/701,496 also claims a priority benefit, under 35U.S.C. §119(e), of U.S. Provisional Patent Application No. 61/151,778,entitled “Marking Device that has a Ticket Management MechanismIntegrated Therein and Associated Methods,” filed on Feb. 11, 2009 underattorney docket no. DYC0017US00.

application Ser. No. 12/701,496 also claims a priority benefit, under 35U.S.C. §120, as a continuation-in-part (CIP) of U.S. Non-provisionalapplication Ser. No. 12/571,356, entitled, “Method And Apparatus ForAnalyzing Locate And Marking Operations With Respect To FacilitiesMaps,” filed on Sep. 30, 2009 under attorney docket no. DYC0012US01.

application Ser. No. 12/571,356 in turn claims a priority benefit, under35 U.S.C. §119(e), of U.S. Provisional Patent Application Ser. No.61/102,169, entitled “Data Acquisition System For And Method OfAnalyzing Locate Operations With Respect To Facilities Maps,” filed onOct. 2, 2008 under attorney docket no. DYC0012US00.

application Ser. No. 12/701,496 also claims a priority benefit, under 35U.S.C. §120, as a continuation-in-part (CIP) of U.S. Non-provisionalapplication Ser. No. 12/649,535, entitled, “Method And Apparatus ForDisplaying an Electronic Rendering of a Locate and/or Marking OperationUsing Display Layers,” filed on Dec. 30, 2009 under attorney docket no.DYC0010US02.

application Ser. No. 12/649,535 in turn claims a priority benefit, under35 U.S.C. §120, as a continuation (CON) of U.S. Non-provisionalapplication Ser. No. 12/569,192, entitled “Methods, Apparatus, andSystems for Generating Electronic Records of Locate and MarkingOperations, and Combined Locate and Marking Apparatus for Same,” filedon Sep. 29, 2009 under attorney docket no. DYC0010US01.

application Ser. No. 12/569,192 in turn claims a priority benefit, under35 U.S.C. §119(e), of U.S. Provisional Application Ser. No. 61/102,122,entitled “Combination Locate and Marking Device With a Data AcquisitionSystem Installed Therein, and Associated Methods,” filed on Oct. 2, 2008under attorney docket no. DYC0010US00.

application Ser. No. 12/569,192 also claims a priority benefit, under 35U.S.C. §120, as a continuation-in-part (CIP) of U.S. Non-provisionalapplication Ser. No. 12/568,087, entitled “Methods and Apparatus forGenerating an Electronic Record of Environmental Landmarks Based onMarking Device Actuations,” filed on Sep. 28, 2009 under attorney docketno. DYC0014US01.

application Ser. No. 12/568,087 in turn claims the benefit, under 35U.S.C. §119(e), of U.S. Provisional Patent Application Ser. No.61/102,205, entitled “Data Acquisition For And Method Of AnalyzingLocate Operations With Respect To Environmental Landmarks,” filed Oct.2, 2008 under attorney docket no. DYC0014US00.

application Ser. No. 12/568,087 also claims a priority benefit, under 35U.S.C. §120, as a continuation-in-part (CIP) of U.S. Non-provisionalapplication Ser. No. 12/539,497, entitled “Methods and Apparatus forGenerating an Electronic Record of a Marking Operation based on MarkingDevice Actuations,” filed on Aug. 11, 2009 under attorney docket no.DYC0011US01.

application Ser. No. 12/539,497 in turn claims the benefit, under 35U.S.C. §119(e), of U.S. Provisional Application Ser. No. 61/102,151,entitled “Data acquisition system for and method of analyzing markingoperations based on marking device actuations,” filed on Oct. 2, 2008under attorney docket no. DYC0011US00.

Each of the above-identified applications is hereby incorporated hereinby reference.

BACKGROUND

Field service operations may be any operation in which companiesdispatch technicians and/or other staff to perform certain activities,for example, installations, services and/or repairs. Field serviceoperations may exist in various industries, examples of which include,but are not limited to, network installations, utility installations,security systems, construction, medical equipment, heating, ventilatingand air conditioning (HVAC) and the like.

An example of a field service operation in the construction industry isa so-called “locate and marking operation,” also commonly referred tomore simply as a “locate operation” (or sometimes merely as “a locate”).In a typical locate operation, a locate technician visits a work site inwhich there is a plan to disturb the ground (e.g., excavate, dig one ormore holes and/or trenches, bore, etc.) so as to determine a presence oran absence of one or more underground facilities (such as various typesof utility cables and pipes) in a dig area to be excavated or disturbedat the work site. In some instances, a locate operation may be requestedfor a “design” project, in which there may be no immediate plan toexcavate or otherwise disturb the ground, but nonetheless informationabout a presence or absence of one or more underground facilities at awork site may be valuable to inform a planning, permitting and/orengineering design phase of a future construction project.

In many states, an excavator who plans to disturb ground at a work siteis required by law to notify any potentially affected undergroundfacility owners prior to undertaking an excavation activity. Advancednotice of excavation activities may be provided by an excavator (oranother party) by contacting a “one-call center.” One-call centerstypically are operated by a consortium of underground facility ownersfor the purposes of receiving excavation notices and in turn notifyingfacility owners and/or their agents of a plan to excavate. As part of anadvanced notification, excavators typically provide to the one-callcenter various information relating to the planned activity, including alocation (e.g., address) of the work site and a description of the digarea to be excavated or otherwise disturbed at the work site.

FIG. 1 illustrates an example in which a locate operation is initiatedas a result of an excavator 1 providing an excavation notice to aone-call center 2. An excavation notice also is commonly referred to asa “locate request,” and may be provided by the excavator to the one-callcenter via an electronic mail message, information entry via a websitemaintained by the one-call center, or a telephone conversation betweenthe excavator and a technician at the one-call center. The locaterequest may include an address or some other location-relatedinformation describing the geographic location of a work site at whichthe excavation is to be performed, as well as a description of the digarea (e.g., a text description), such as its location relative tocertain landmarks and/or its approximate dimensions, within which thereis a plan to disturb the ground at the work site. One-call centerssimilarly may receive locate requests for design projects (for which, asdiscussed above, there may be no immediate plan to excavate or otherwisedisturb the ground).

Using the information provided in a locate request for plannedexcavation or design projects, the one-call center identifies certainunderground facilities that may be present at the indicated work site.For this purpose, many one-call centers typically maintain a collection“polygon maps” which indicate, within a given geographic area over whichthe one-call center has jurisdiction, generally where undergroundfacilities may be found relative to some geographic reference frame orcoordinate system.

Polygon maps typically are provided to the one-call centers byunderground facilities owners within the jurisdiction of the one callcenter (“members” of the one-call center). A one-call center firstprovides the facility owner/member with one or more maps (e.g., streetor property maps) within the jurisdiction, on which are superimposedsome type of grid or coordinate system employed by the one-call centeras a geographic frame of reference. Using the maps provided by theone-call center, the respective facilities owners/members draw one ormore polygons on each map to indicate an area within which theirfacilities generally are disposed underground (without indicating thefacilities themselves). These polygons themselves do not preciselyindicate geographic locations of respective underground facilities;rather, the area enclosed by a given polygon generally provides anover-inclusive indication of where a given facilities owner'sunderground facilities are disposed. Different facilities owners/membersmay draw polygons of different sizes around areas including theirunderground facilities, and in some instances such polygons can coverappreciably large geographic regions (e.g., an entire subdivision of aresidential area), which may further obfuscate the actual/preciselocation of respective underground facilities.

Based on the polygon maps collected from the facilities owners/members,the one-call center may in some instances create composite polygon mapsto show polygons of multiple different members on a single map. Whetherusing single member or composite polygon maps, the one-call centerexamines the address or location information provided in the locaterequest and identifies a significant buffer zone around an identifiedwork site so as to make an over-inclusive identification of facilitiesowners/members that may have underground facilities present (e.g., toerr on the side of caution). In particular, based on this generallyover-inclusive buffer zone around the identified work site (and in someinstances significantly over-inclusive buffer zone), the one-call centerconsults the polygon maps to identify which member polygons intersectwith all or a portion of the buffer zone so as to notify theseunderground facility owners/members and/or their agents of the proposedexcavation or design project. Again, it should be appreciated that thebuffer zones around an indicated work site utilized by one-call centersfor this purpose typically embrace a geographic area that includes butgoes well beyond the actual work site, and in many cases the geographicarea enclosed by a buffer zone is significantly larger than the actualdig area in which excavation or other similar activities are planned.Similarly, as noted above, the area enclosed by a given member polygongenerally does not provide a precise indication of where one or moreunderground facilities may in fact be found.

In some instances, one-call centers may also or alternatively haveaccess to various existing maps of underground facilities in theirjurisdiction, referred to as “facilities maps.” Facilities mapstypically are maintained by facilities owners/members within thejurisdiction and show, for respective different utility types, whereunderground facilities purportedly may be found relative to somegeographic reference frame or coordinate system (e.g., a grid, a streetor property map, GPS latitude and longitude coordinates, etc.).Facilities maps generally provide somewhat more detail than polygon mapsprovided by facilities owners/members; however, in some instances theinformation contained in facilities maps may not be accurate and/orcomplete. For at least this reason, whether using polygon maps orfacilities maps, as noted above the one-call center utilizes asignificant buffer zone around an identified work site so as to make anover-inclusive identification of facilities owners/members that may haveunderground facilities present.

Once facilities implicated by the locate request are identified by aone-call center (e.g., via the polygon map/buffer zone process), theone-call center generates a “locate request ticket” (also known as a“locate ticket,” or simply a “ticket”). The locate request ticketessentially constitutes an instruction to inspect a work site andtypically identifies the work site of the proposed excavation or designand a description of the dig area, typically lists on the ticket all ofthe underground facilities that may be present at the work site (e.g.,by providing a member code for the facility owner whose polygon fallswithin a given buffer zone), and may also include various otherinformation relevant to the proposed excavation or design (e.g., thename of the excavation company, a name of a property owner or partycontracting the excavation company to perform the excavation, etc.). Theone-call center sends the ticket to one or more underground facilityowners 4 and/or one or more locate service providers 3 (who may beacting as contracted agents of the facility owners) so that they canconduct a locate and marking operation to verify a presence or absenceof the underground facilities in the dig area. For example, in someinstances, a given underground facility owner 4 may operate its ownfleet of locate technicians (e.g., locate technician 6), in which casethe one-call center 2 may send the ticket to the underground facilityowner 4. In other instances, a given facility owner may contract with alocate service provider to receive locate request tickets and perform alocate and marking operation in response to received tickets on theirbehalf.

Upon receiving the locate request, a locate service provider or afacility owner (hereafter referred to as a “ticket recipient”) maydispatch a locate technician 5 to the work site of planned excavation todetermine a presence or absence of one or more underground facilities inthe dig area to be excavated or otherwise disturbed. A typical firststep for the locate technician 5 includes utilizing an undergroundfacility “locate device,” which is an instrument or set of instruments(also referred to commonly as a “locate set”) for detecting facilitiesthat are concealed in some manner, such as cables and pipes that arelocated underground. The locate device is employed by the technician toverify the presence or absence of underground facilities indicated inthe locate request ticket as potentially present in the dig area (e.g.,via the facility owner member codes listed in the ticket). This processis often referred to as a “locate operation.”

In one example of a locate operation, an underground facility locatedevice is used to detect electromagnetic fields that are generated by anapplied signal provided along a length of a target facility to beidentified. In this example, a locate device may include both a signaltransmitter to provide the applied signal (e.g., which is coupled by thelocate technician to a tracer wire disposed along a length of afacility), and a signal receiver which is generally a hand-heldapparatus carried by the locate technician as the technician walksaround the dig area to search for underground facilities. FIG. 2illustrates a conventional locate device 20 (indicated by the dashedbox) that includes a transmitter 22 and a locate receiver 24. Thetransmitter 22 is connected, via a connection point 26, to a targetobject (in this example, underground facility 28) located in the ground21. The transmitter generates the applied signal 23, which is coupled tothe underground facility via the connection point (e.g., to a tracerwire along the facility), resulting in the generation of a magneticfield 25. The magnetic field in turn is detected by the locate receiver24, which itself may include one or more detection antenna (not shown).The locate receiver 24 indicates a presence of a facility when itdetects electromagnetic fields arising from the applied signal 23.Conversely, the absence of a signal detected by the locate receivergenerally indicates the absence of the target facility.

In yet another example, a locate device employed for a locate operationmay include a single instrument, similar in some respects to aconventional metal detector. In particular, such an instrument mayinclude an oscillator to generate an alternating current that passesthrough a coil, which in turn produces a first magnetic field. If apiece of electrically conductive metal is in close proximity to the coil(e.g., if an underground facility having a metal component is below/nearthe coil of the instrument), eddy currents are induced in the metal andthe metal produces its own magnetic field, which in turn affects thefirst magnetic field. The instrument may include a second coil tomeasure changes to the first magnetic field, thereby facilitatingdetection of metallic objects.

In addition to the locate operation, the locate technician alsogenerally performs a “marking operation,” in which the technician marksthe presence (and in some cases the absence) of a given undergroundfacility in the dig area based on the various signals detected (or notdetected) during the locate operation. For this purpose, the locatetechnician conventionally utilizes a “marking device” to dispense amarking material on, for example, the ground, pavement, or other surfacealong a detected underground facility. Marking material may be anymaterial, substance, compound, and/or element, used or which may be usedseparately or in combination to mark, signify, and/or indicate. Examplesof marking materials may include, but are not limited to, paint, chalk,dye, and/or iron. Marking devices, such as paint marking wands and/orpaint marking wheels, provide a convenient method of dispensing markingmaterials onto surfaces, such as onto the surface of the ground orpavement.

FIGS. 3A and 3B illustrate a conventional marking device 50 with amechanical actuation system to dispense paint as a marker. Generallyspeaking, the marking device 50 includes a handle 38 at a proximal endof an elongated shaft 36 and resembles a sort of “walking stick,” suchthat a technician may operate the marking device while standing/walkingin an upright or substantially upright position. A marking dispenserholder 40 is coupled to a distal end of the shaft 36 so as to containand support a marking dispenser 56, e.g., an aerosol paint can having aspray nozzle 54. Typically, a marking dispenser in the form of anaerosol paint can is placed into the holder 40 upside down, such thatthe spray nozzle 54 is proximate to the distal end of the shaft (closeto the ground, pavement or other surface on which markers are to bedispensed).

In FIGS. 3A and 3B, the mechanical actuation system of the markingdevice 50 includes an actuator or mechanical trigger 42 proximate to thehandle 38 that is actuated/triggered by the technician (e.g., viapulling, depressing or squeezing with fingers/hand). The actuator 42 isconnected to a mechanical coupler 52 (e.g., a rod) disposed inside andalong a length of the elongated shaft 36. The coupler 52 is in turnconnected to an actuation mechanism 58, at the distal end of the shaft36, which mechanism extends outward from the shaft in the direction ofthe spray nozzle 54. Thus, the actuator 42, the mechanical coupler 52,and the actuation mechanism 58 constitute the mechanical actuationsystem of the marking device 50.

FIG. 3A shows the mechanical actuation system of the conventionalmarking device 50 in the non-actuated state, wherein the actuator 42 is“at rest” (not being pulled) and, as a result, the actuation mechanism58 is not in contact with the spray nozzle 54. FIG. 3B shows the markingdevice 50 in the actuated state, wherein the actuator 42 is beingactuated (pulled, depressed, squeezed) by the technician. When actuated,the actuator 42 displaces the mechanical coupler 52 and the actuationmechanism 58 such that the actuation mechanism contacts and appliespressure to the spray nozzle 54, thus causing the spray nozzle todeflect slightly and dispense paint. The mechanical actuation system isspring-loaded so that it automatically returns to the non-actuated state(FIG. 3A) when the actuator 42 is released.

In some environments, arrows, flags, darts, or other types of physicalmarks may be used to mark the presence or absence of an undergroundfacility in a dig area, in addition to or as an alternative to amaterial applied to the ground (such as paint, chalk, dye, tape) alongthe path of a detected utility. The marks resulting from any of a widevariety of materials and/or objects used to indicate a presence orabsence of underground facilities generally are referred to as “locatemarks.” Often, different color materials and/or physical objects may beused for locate marks, wherein different colors correspond to differentutility types. For example, the American Public Works Association (APWA)has established a standardized color-coding system for utilityidentification for use by public agencies, utilities, contractors andvarious groups involved in ground excavation (e.g., red=electric powerlines and cables; blue=potable water; orange=telecommunication lines;yellow=gas, oil, steam). In some cases, the technician also may provideone or more marks to indicate that no facility was found in the dig area(sometimes referred to as a “clear”).

As mentioned above, the foregoing activity of identifying and marking apresence or absence of one or more underground facilities generally isreferred to for completeness as a “locate and marking operation.”However, in light of common parlance adopted in the constructionindustry, and/or for the sake of brevity, one or both of the respectivelocate and marking functions may be referred to in some instances simplyas a “locate operation” or a “locate” (i.e., without making any specificreference to the marking function). Accordingly, it should beappreciated that any reference in the relevant arts to the task of alocate technician simply as a “locate operation” or a “locate” does notnecessarily exclude the marking portion of the overall process. At thesame time, in some contexts a locate operation is identified separatelyfrom a marking operation, wherein the former relates more specificallyto detection-related activities and the latter relates more specificallyto marking-related activities.

Inaccurate locating and/or marking of underground facilities can resultin physical damage to the facilities, property damage, and/or personalinjury during the excavation process that, in turn, can expose afacility owner or contractor to significant legal liability. Whenunderground facilities are damaged and/or when property damage orpersonal injury results from damaging an underground facility during anexcavation, the excavator may assert that the facility was notaccurately located and/or marked by a locate technician, while thelocate contractor who dispatched the technician may in turn assert thatthe facility was indeed properly located and marked. Proving whether theunderground facility was properly located and marked can be difficultafter the excavation (or after some damage, e.g., a gas explosion),because in many cases the physical locate marks (e.g., the markingmaterial or other physical marks used to mark the facility on thesurface of the dig area) will have been disturbed or destroyed duringthe excavation process (and/or damage resulting from excavation).

SUMMARY

The inventors have appreciated that, at least in some circumstances,advance knowledge of existing facilities that may be present at a worksite/dig area for a proposed excavation may be useful to a techniciandispatched to perform a locate and/or marking operation. In thisrespect, facilities maps may be a valuable resource to the technician;as noted above, facilities maps generally are maintained by variousfacilities owners and these maps typically indicate the type andgeographic location of one or more facility lines (e.g., pipes, cables,and the like) owned and/or operated by the facility owner(s). Althoughthe accuracy of facilities maps may in some cases be suspect (e.g., dueto incorrect information in the maps, age of the maps, lack of timelyrevisions that reflect the current status of deployed facilities, etc.),the various information present in many types of facilities mapsgenerally provides at least some meaningful orientation to thedeployment of underground facilities in a given area.

Accordingly, the inventors have recognized and appreciated that readyaccess to available facilities maps pertaining to a given work site/digarea may provide the technician with helpful information towardeffectively and efficiently conducting a locate and/or markingoperation. To this end, a library of facilities maps pertaining tovarious types of facilities in a given geographic area may be providedto a locate technician dispatched to the field to perform a locateand/or marking operation. For example, a library of appropriatefacilities maps may be available for viewing electronically via acomputer available at a particular work site (e.g., a laptop computer orother mobile computer disposed in the technician's vehicle).Alternatively, the locate technician may carry with them a set of paperfacilities maps in his/her vehicle. The locate technician may review thefacilities maps in their vehicle, for example, then proceed to theactual dig area to perform the locate and/or marking operation whileattempting to remember relevant information in the facilities maps.However, especially for complex facilities maps, it may be difficult forthe technician to commit to memory relevant information in thefacilities maps, and it may be inconvenient for the technician to returnto the vehicle to consult facilities maps once a locate and/or markingoperation has begun.

In view of the foregoing, various embodiments of the present inventionare directed to methods and apparatus for viewing facilities mapsinformation on a marking device used to conduct a marking operation. Inthis manner, a technician may have access to, and may view locally(e.g., immediately before, during and/or after conducting a locateand/or marking operation in a given work site/dig area), variousinformation derived from facilities maps. For purposes of the presentdisclosure, and as discussed in greater detail herein, “facilities mapsinformation” refers to any information that may be derived from afacilities map, examples of which information include, but are notlimited to, all or a portion of the imagery associated with a facilitiesmap, any underlying metadata (e.g., GIS metadata, facility typeinformation, line or symbol codes, etc.) that may accompany a facilitiesmap or set of facilities maps, and any legend information that may beincluded in a facilities map.

In various aspects, the inventive concepts discussed herein generallyrelate to one of more of the following: 1) selection, from a local orremote library/archive, of one or more appropriate “base” facilitiesmaps or database(s) of facility map data relating to a given worksite/dig area; 2) manual or automated selection of an appropriate panand/or zoom (resolution) for displaying, on a user interface/display ofa marking device, facilities map information derived from the basefacilities map(s); 3) appropriately updating (e.g., changing pan, zoom,orientation, etc.), if/as necessary, displayed facilities mapinformation while a marking device is used during a marking operation;4) overlaying, on the displayed facilities map information, markinginformation relating to the marking operation; and 5) storing locally onthe marking device, and/or transmitting from the marking device,facilities map information and/or overlaid marking information (e.g.,for further processing, analysis and/or subsequent display).

Some examples of marking devices configured to collect variousinformation relating specifically to marking operations, which markingdevices may be modified according to the inventive concepts describedherein to facilitate display of facilities map information, are providedin U.S. publication no. 2008-0228294-A1, published Sep. 18, 2008, filedMar. 13, 2007, and entitled “Marking System and Method With Locationand/or Time Tracking,” U.S. publication no. 2008-0245299-A1, publishedOct. 9, 2008, filed Apr. 4, 2007, and entitled “Marking System andMethod,” and U.S. publication no. 2009-0204238-A1, published Aug. 13,2009, filed Feb. 2, 2009, and entitled “Electronically ControlledMarking Apparatus and Methods,” all of which publications areincorporated herein by reference. These publications describe, amongstother things, collecting information relating to the geographiclocation, time, and/or characteristics (e.g., color/type) of dispensedmarking material from a marking device and generating an electronicrecord based on this collected information. It should be appreciated,however, that the inventive concepts discussed herein in connection withdisplay of facilities map information may be applied generally tovarious instrumentation/equipment used for one or both of a locateoperation and a marking operation (e.g., a marking device, a locatedevice such as a locate transmitter and/or locate receiver, a combinedlocate and marking device, etc.), as discussed in further detail below.An example of combined locate and marking device in which the inventiveconcepts discussed below may be implemented is described in U.S.Non-provisional application Ser. No. 12/569,192, entitled “Methods,Apparatus, and Systems for Generating Electronic Records of Locate andMarking Operations, and Combined Locate and Marking Apparatus for Same,”filed on Sep. 29, 2009 under attorney docket no. D0687.70010US01.

Similarly, it should be appreciated that pursuant to the inventiveconcepts described herein, facilities map information displayed on amarking device may facilitate execution of either or both of a locateoperation and a marking operation, as at least in some instances atechnician would have at their disposal, and use together, both a locatedevice and a marking device to detect and mark a presence or absence ofone or more underground facilities at a work site/dig area.

Furthermore, in addition to facilities map information, it should beappreciated that the present disclosure contemplates other types ofimage information being accessed and displayed on a userinterface/display of a marking device to facilitate various aspects of alocate and/or marking operation. For example, other types of maps (e.g.,street/road maps, polygon maps, tax maps, etc.), architectural,construction and/or engineering drawings, land surveys, and photographicrenderings/images, and various information derived therefrom, may bedisplayed on the marking device and may also be used as the basis foroverlaying marking information relating to a marking operation. As withfacilities map information, such image information and/or overlaidmarking information may be stored locally on the marking device, and/ortransmitted from the marking device (e.g., for further processing,analysis and/or subsequent display).

In sum, one embodiment of the present invention is directed to a markingapparatus to mark a presence or an absence of an underground facility.The marking apparatus comprises: a housing; a marking dispenser holdercoupled to the housing to hold a replaceable marking material; anactuator that, when actuated, causes dispensing of the marking material;a display device coupled to the housing; at least one memory; and atleast one processor, communicatively coupled to the display device andthe at least one memory, and configured to display on the display devicea map image that is generated based on first map data selected by the atleast one processor.

Another embodiment is directed to a method for displaying information ona marking apparatus having a housing, a marking dispenser holder coupledto the housing to hold a replaceable marking material, an actuator that,when actuated, causes dispensing of the marking material, a displaydevice coupled to the housing, at least one memory, and at least oneprocessor, coupled to the display device and the at least one memory.The method comprises displaying on the display device a map image thatis generated based on first map data selected by the at least oneprocessor.

Another embodiment is directed to at least one computer-readable storagemedium encoded with instructions that, when executed on at least oneprocessor in marking apparatus having a housing, a marking dispenserholder coupled to the housing to hold a replaceable marking material, anactuator that, when actuated, causes dispensing of the marking material,a display device coupled to the processor and the housing, and at leastone memory coupled to the at least one processor, causes the at leastone processor to perform a method comprising displaying on the displaydevice a map image that is generated based on first map data selected bythe at least one processor.

Another embodiment is directed to a marking apparatus to mark a presenceor an absence of an underground facility. The marking apparatuscomprises: a housing; a marking dispenser holder coupled to the housingto hold a replaceable marking material; an actuator that, when actuated,causes dispensing of the marking material; a display device coupled tothe housing; at least one memory; and at least one processor,communicatively coupled to the display device and the at least onememory, and configured to: display on the display device a map imagethat is generated based on first map data selected by the at least oneprocessor and that includes a geographic location at which the markingapparatus has dispensed the marking material; and overlay an electronicrepresentation of the marking material on the first map image at aposition on the first map image corresponding to a location at which themarking material was dispensed.

Another embodiment is directed to a method for displaying information ona marking apparatus having a housing, a marking dispenser holder coupledto the housing to hold a replaceable marking material, an actuator that,when actuated, causes dispensing of the marking material, a displaydevice coupled to the housing, at least one memory, and at least oneprocessor, coupled to the display device and the at least one memory.The method comprises: displaying on the display device a map image thatis generated based on first map data selected by the at least oneprocessor and that includes a geographic location at which the markingapparatus has dispensed the marking material; and overlaying anelectronic representation of the marking material on the first map imageat a position on the first map image corresponding to a location atwhich the marking material was dispensed.

Another embodiment is directed to at least one computer-readable storagemedium encoded with instructions that, when executed on at least oneprocessor in marking apparatus having a housing, a marking dispenserholder coupled to the housing to hold a replaceable marking material, anactuator that, when actuated, causes dispensing of the marking material,a display device coupled to the processor and the housing, and at leastone memory coupled to the at least one processor, causes the at leastone processor to perform a method comprising: displaying on the displaydevice a map image that is generated based on first map data selected bythe at least one processor and that includes a geographic location atwhich the marking apparatus has dispensed the marking material; andoverlaying an electronic representation of the marking material on thefirst map image at a position on the first map image corresponding to alocation at which the marking material was dispensed.

Another embodiment is directed to a marking apparatus to mark a presenceor an absence of an underground facility. The marking apparatuscomprises: a housing; a marking dispenser holder coupled to the housingto hold a replaceable marking material; an actuator that, when actuated,causes dispensing of the marking material; a display device coupled tothe housing; at least one memory; and at least one processor,communicatively coupled to the display device and the at least onememory, and configured to: display on the display device a map imagethat is generated based on first map data that comprises facilities mapdata and is selected by the at least one processor; and compare alocation at which marking material was dispensed to a location of afacility line as indicated by the first map data and generate an alertbased on the comparison.

Another embodiment is directed to a method for displaying information ona marking apparatus having a housing, a marking dispenser holder coupledto the housing to hold a replaceable marking material, an actuator that,when actuated, causes dispensing of the marking material, a displaydevice coupled to the housing, at least one memory, and at least oneprocessor, coupled to the display device and the at least one memory.The method comprises displaying on the display device a map image thatis generated based on first map data that comprises facilities map dataand is selected by the at least one processor; and comparing a locationat which marking material was dispensed to a location of a facility lineas indicated by the first map data and generating an alert based on thecomparison.

Another embodiment is directed to at least one computer-readable storagemedium encoded with instructions that, when executed on at least oneprocessor in marking apparatus having a housing, a marking dispenserholder coupled to the housing to hold a replaceable marking material, anactuator that, when actuated, causes dispensing of the marking material,a display device coupled to the processor and the housing, and at leastone memory coupled to the at least one processor, causes the at leastone processor to perform a method comprising: displaying on the displaydevice a map image that is generated based on first map data thatcomprises facilities map data and is selected by the at least oneprocessor; and comparing a location at which marking material wasdispensed to a location of a facility line as indicated by the first mapdata and generating an alert based on the comparison.

For purposes of the present disclosure, the term “dig area” refers to aspecified area of a work site within which there is a plan to disturbthe ground (e.g., excavate, dig holes and/or trenches, bore, etc.), andbeyond which there is no plan to excavate in the immediate surroundings.Thus, the metes and bounds of a dig area are intended to providespecificity as to where some disturbance to the ground is planned at agiven work site. It should be appreciated that a given work site mayinclude multiple dig areas.

The term “facility” refers to one or more lines, cables, fibers,conduits, transmitters, receivers, or other physical objects orstructures capable of or used for carrying, transmitting, receiving,storing, and providing utilities, energy, data, substances, and/orservices, and/or any combination thereof. The term “undergroundfacility” means any facility beneath the surface of the ground. Examplesof facilities include, but are not limited to, oil, gas, water, sewer,power, telephone, data transmission, cable television (TV), and/orinternet services.

The term “locate device” refers to any apparatus and/or device fordetecting and/or inferring the presence or absence of any facility,including without limitation, any underground facility. In variousexamples, a locate device may include both a locate transmitter and alocate receiver (which in some instances may also be referred tocollectively as a “locate instrument set,” or simply “locate set”).

The term “marking device” refers to any apparatus, mechanism, or otherdevice that employs a marking dispenser for causing a marking materialand/or marking object to be dispensed, or any apparatus, mechanism, orother device for electronically indicating (e.g., logging in memory) alocation, such as a location of an underground facility. Additionally,the term “marking dispenser” refers to any apparatus, mechanism, orother device for dispensing and/or otherwise using, separately or incombination, a marking material and/or a marking object. An example of amarking dispenser may include, but is not limited to, a pressurized canof marking paint. The term “marking material” means any material,substance, compound, and/or element, used or which may be usedseparately or in combination to mark, signify, and/or indicate. Examplesof marking materials may include, but are not limited to, paint, chalk,dye, and/or iron. The term “marking object” means any object and/orobjects used or which may be used separately or in combination to mark,signify, and/or indicate. Examples of marking objects may include, butare not limited to, a flag, a dart, and arrow, and/or an RFID markingball. It is contemplated that marking material may include markingobjects. It is further contemplated that the terms “marking materials”or “marking objects” may be used interchangeably in accordance with thepresent disclosure.

The term “locate mark” means any mark, sign, and/or object employed toindicate the presence or absence of any underground facility. Examplesof locate marks may include, but are not limited to, marks made withmarking materials, marking objects, global positioning or otherinformation, and/or any other means. Locate marks may be represented inany form including, without limitation, physical, visible, electronic,and/or any combination thereof.

The terms “actuate” or “trigger” (verb form) are used interchangeably torefer to starting or causing any device, program, system, and/or anycombination thereof to work, operate, and/or function in response tosome type of signal or stimulus. Examples of actuation signals orstimuli may include, but are not limited to, any local or remote,physical, audible, inaudible, visual, non-visual, electronic,mechanical, electromechanical, biomechanical, biosensing or othersignal, instruction, or event. The terms “actuator” or “trigger” (nounform) are used interchangeably to refer to any method or device used togenerate one or more signals or stimuli to cause or causing actuation.Examples of an actuator/trigger may include, but are not limited to, anyform or combination of a lever, switch, program, processor, screen,microphone for capturing audible commands, and/or other device ormethod. An actuator/trigger may also include, but is not limited to, adevice, software, or program that responds to any movement and/orcondition of a user, such as, but not limited to, eye movement, brainactivity, heart rate, other data, and/or the like, and generates one ormore signals or stimuli in response thereto. In the case of a markingdevice or other marking mechanism (e.g., to physically or electronicallymark a facility or other feature), actuation may cause marking materialto be dispensed, as well as various data relating to the markingoperation (e.g., geographic location, time stamps, characteristics ofmaterial dispensed, etc.) to be logged in an electronic file stored inmemory. In the case of a locate device or other locate mechanism (e.g.,to physically locate a facility or other feature), actuation may cause adetected signal strength, signal frequency, depth, or other informationrelating to the locate operation to be logged in an electronic filestored in memory.

The terms “locate and marking operation,” “locate operation,” and“locate” generally are used interchangeably and refer to any activity todetect, infer, and/or mark the presence or absence of an undergroundfacility. In some contexts, the term “locate operation” is used to morespecifically refer to detection of one or more underground facilities,and the term “marking operation” is used to more specifically refer tousing a marking material and/or one or more marking objects to mark apresence or an absence of one or more underground facilities. The term“locate technician” refers to an individual performing a locateoperation. A locate and marking operation often is specified inconnection with a dig area, at least a portion of which may be excavatedor otherwise disturbed during excavation activities.

The term “user” refers to an individual utilizing a locate device and/ora marking device and may include, but is not limited to, land surveyors,locate technicians, and support personnel.

The terms “locate request” and “excavation notice” are usedinterchangeably to refer to any communication to request a locate andmarking operation. The term “locate request ticket” (or simply “ticket”)refers to any communication or instruction to perform a locateoperation. A ticket might specify, for example, the address ordescription of a dig area to be marked, the day and/or time that the digarea is to be marked, and/or whether the user is to mark the excavationarea for certain gas, water, sewer, power, telephone, cable television,and/or some other underground facility. The term “historical ticket”refers to past tickets that have been completed.

The following U.S. published applications and patents are herebyincorporated herein by reference:

-   U.S. Pat. No. 7,640,105, issued Dec. 29, 2009, filed Mar. 13, 2007,    and entitled “Marking System and Method With Location and/or Time    Tracking;”-   U.S. publication no. 2008-0245299-A1, published Oct. 9, 2008, filed    Apr. 4, 2007, and entitled “Marking System and Method;”-   U.S. publication no. 2009-0013928-A1, published Jan. 15, 2009, filed    Sep. 24, 2008, and entitled “Marking System and Method;”-   U.S. publication no. 2009-0238414-A1, published Sep. 24, 2009, filed    Mar. 18, 2008, and entitled “Virtual White Lines for Delimiting    Planned Excavation Sites;”-   U.S. publication no. 2009-0241045-A1, published Sep. 24, 2009, filed    Sep. 26, 2008, and entitled “Virtual White Lines for Delimiting    Planned Excavation Sites;”-   U.S. publication no. 2009-0238415-A1, published Sep. 24, 2009, filed    Sep. 26, 2008, and entitled “Virtual White Lines for Delimiting    Planned Excavation Sites;”-   U.S. publication no. 2009-0241046-A1, published Sep. 24, 2009, filed    Jan. 16, 2009, and entitled “Virtual White Lines for Delimiting    Planned Excavation Sites;”-   U.S. publication no. 2009-0238416-A1, published Sep. 24, 2009, filed    Jan. 16, 2009, and entitled “Virtual White Lines for Delimiting    Planned Excavation Sites;”-   U.S. publication no. 2009-0237408-A1, published Sep. 24, 2009, filed    Jan. 16, 2009, and entitled “Virtual White Lines for Delimiting    Planned Excavation Sites;”-   U.S. publication no. 2009-0202101-A1, published Aug. 13, 2009, filed    Feb. 12, 2008, and entitled “Electronic Manifest of Underground    Facility Locate Marks;”-   U.S. publication no. 2009-0202110-A1, published Aug. 13, 2009, filed    Sep. 11, 2008, and entitled “Electronic Manifest of Underground    Facility Locate Marks;”-   U.S. publication no. 2009-0201311-A1, published Aug. 13, 2009, filed    Jan. 30, 2009, and entitled “Electronic Manifest of Underground    Facility Locate Marks;”-   U.S. publication no. 2009-0202111-A1, published Aug. 13, 2009, filed    Jan. 30, 2009, and entitled “Electronic Manifest of Underground    Facility Locate Marks;”-   U.S. publication no. 2009-0204625-A1, published Aug. 13, 2009, filed    Feb. 5, 2009, and entitled “Electronic Manifest of Underground    Facility Locate Operation;”-   U.S. publication no. 2009-0204466-A1, published Aug. 13, 2009, filed    Sep. 4, 2008, and entitled “Ticket Approval System For and Method of    Performing Quality Control In Field Service Applications;”-   U.S. publication no. 2009-0207019-A1, published Aug. 20, 2009, filed    Apr. 30, 2009, and entitled “Ticket Approval System For and Method    of Performing Quality Control In Field Service Applications;”-   U.S. publication no. 2009-0210284-A1, published Aug. 20, 2009, filed    Apr. 30, 2009, and entitled “Ticket Approval System For and Method    of Performing Quality Control In Field Service Applications;”-   U.S. publication no. 2009-0210297-A1, published Aug. 20, 2009, filed    Apr. 30, 2009, and entitled “Ticket Approval System For and Method    of Performing Quality Control In Field Service Applications;”-   U.S. publication no. 2009-0210298-A1, published Aug. 20, 2009, filed    Apr. 30, 2009, and entitled “Ticket Approval System For and Method    of Performing Quality Control In Field Service Applications;”-   U.S. publication no. 2009-0210285-A1, published Aug. 20, 2009, filed    Apr. 30, 2009, and entitled “Ticket Approval System For and Method    of Performing Quality Control In Field Service Applications;”-   U.S. publication no. 2009-0324815-A1, published Dec. 31, 2009, filed    Apr. 24, 2009, and entitled “Marking Apparatus and Marking Methods    Using Marking Dispenser with Machine-Readable ID Mechanism;”-   U.S. publication no. 2010-0006667-A1, published Jan. 14, 2010, filed    Apr. 24, 2009, and entitled, “Marker Detection Mechanisms for use in    Marking Devices And Methods of Using Same;”-   U.S. publication no. 2009-0204238-A1, published Aug. 13, 2009, filed    Feb. 2, 2009, and entitled “Electronically Controlled Marking    Apparatus and Methods;”-   U.S. publication no. 2009-0208642-A1, published Aug. 20, 2009, filed    Feb. 2, 2009, and entitled “Marking Apparatus and Methods For    Creating an Electronic Record of Marking Operations;”-   U.S. publication no. 2009-0210098-A1, published Aug. 20, 2009, filed    Feb. 2, 2009, and entitled “Marking Apparatus and Methods For    Creating an Electronic Record of Marking Apparatus Operations;”-   U.S. publication no. 2009-0201178-A1, published Aug. 13, 2009, filed    Feb. 2, 2009, and entitled “Methods For Evaluating Operation of    Marking Apparatus;”-   U.S. publication no. 2009-0238417-A1, published Sep. 24, 2009, filed    Feb. 6, 2009, and entitled “Virtual White Lines for Indicating    Planned Excavation Sites on Electronic Images;”-   U.S. publication no. 2009-0202112-A1, published Aug. 13, 2009, filed    Feb. 11, 2009, and entitled “Searchable Electronic Records of    Underground Facility Locate Marking Operations;”-   U.S. publication no. 2009-0204614-A1, published Aug. 13, 2009, filed    Feb. 11, 2009, and entitled “Searchable Electronic Records of    Underground Facility Locate Marking Operations;”-   U.S. publication no. 2009-0327024-A1, published Dec. 31, 2009, filed    Jun. 26, 2009, and entitled “Methods and Apparatus for Quality    Assessment of a Field Service Operation;”-   U.S. publication no. 2010-0010862-A1, published Jan. 14, 2010, filed    Aug. 7, 2009, and entitled, “Methods and Apparatus for Quality    Assessment of a Field Service Operation Based on Geographic    Information;”-   U.S. publication No. 2010-0010863-A1, published Jan. 14, 2010, filed    Aug. 7, 2009, and entitled, “Methods and Apparatus for Quality    Assessment of a Field Service Operation Based on Multiple Scoring    Categories;”-   U.S. publication no. 2010-0010882-A1, published Jan. 14, 2010, filed    Aug. 7, 2009, and entitled, “Methods and Apparatus for Quality    Assessment of a Field Service Operation Based on Dynamic Assessment    Parameters;” and-   U.S. publication no. 2010-0010883-A1, published Jan. 14, 2010, filed    Aug. 7, 2009, and entitled, “Methods and Apparatus for Quality    Assessment of a Field Service Operation Based on Multiple Quality    Assessment Criteria.”

It should be appreciated that all combinations of the foregoing conceptsand additional concepts discussed in greater detail below (provided suchconcepts are not mutually inconsistent) are contemplated as being partof the inventive subject matter disclosed herein. In particular, allcombinations of claimed subject matter appearing at the end of thisdisclosure are contemplated as being part of the inventive subjectmatter disclosed herein. It should also be appreciated that terminologyexplicitly employed herein that also may appear in any disclosureincorporated by reference should be accorded a meaning most consistentwith the particular concepts disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings are not necessarily to scale, emphasis instead generallybeing placed upon illustrating the principles of the invention.

FIG. 1 shows an example in which a locate and marking operation isinitiated as a result of an excavator providing an excavation notice toa one-call center.

FIG. 2 illustrates one example of a conventional locate instrument setincluding a locate transmitter and a locate receiver.

FIGS. 3A and 3B illustrate a conventional marking device in an actuatedand non-actuated state, respectively.

FIG. 4 is a functional block diagram of a data acquisition systemincluding a marking device for creating electronic records of markingoperations and displaying facilities map information, according to someembodiments of the present invention.

FIG. 5 is a perspective view of the data acquisition system of FIG. 4,illustrating an exemplary marking device upon which some embodiments ofthe invention may be implemented.

FIGS. 6A and 6B illustrate a portion of an actuation system of themarking device of FIG. 5.

FIG. 7 illustrates various components of the actuation system of FIGS.6A and 6B.

FIG. 8 illustrates an example of facilities map information that may beviewed on the display of the marking device.

FIG. 9 illustrates a sketch representing an exemplary input image thatmay be viewed on the display of the marking device.

FIG. 10 illustrates a map, representing an exemplary input image thatmay be viewed on the display of the marking device.

FIG. 11 illustrates a construction/engineering drawing, representing anexemplary input image that may be viewed on the display of the markingdevice.

FIG. 12 illustrates a land survey map, representing an exemplary inputimage that may be viewed on the display of the marking device.

FIG. 13 illustrates a grid, overlaid on the construction/engineeringdrawing of FIG. 11, representing an exemplary input image that may beviewed on the display of the marking device.

FIG. 14 illustrates a street level image, representing an exemplaryinput image that may be viewed on the display of the marking device.

FIG. 15 illustrates an example of a video frame sequence of a facilitiesmap that may be displayed on the display of a marking device, inaccordance with some embodiments.

FIG. 16 illustrates a flow diagram of a process for displaying afacilities map on the display of a marking device, in accordance withsome embodiments.

FIG. 17 illustrates a flow diagram of a process for overlaying data on afacilities map displayed on the display of a marking device.

FIG. 18 shows a display device having a display field in which one ormore display layers and/or sub-layers of marking information, landmarkinformation and/or image/reference information may be selectivelyenabled or disabled for display, according to one embodiment of thepresent invention.

DETAILED DESCRIPTION

Following below are more detailed descriptions of various conceptsrelated to, and embodiments of, inventive systems, methods and apparatusfor viewing facilities maps information and/or other image informationon a marking device. It should be appreciated that various conceptsintroduced above and discussed in greater detail below may beimplemented in any of numerous ways, as the disclosed concepts are notlimited to any particular manner of implementation. Examples of specificimplementations and applications are provided primarily for illustrativepurposes.

Various embodiments of the present invention relate to a marking devicecapable of accessing and displaying various types of information derivedfrom one or more facilities maps. In some embodiments, the markingdevice may have the capability to access one or more locally and/orremotely stored electronic facilities maps or a database of facilitiesmap information, and select and display all or a portion of a facilitiesmap that is of interest to a technician or other technician of themarking device. As explained in detail below, in some embodiments, themarking device may update the display of the facilities map informationin essentially real-time (e.g., change one or more of pan, zoom,orientation, etc.), as the marking device is in use, when changes in thegeo-location and/or heading of the marking device are detected. In thismanner, the marking device provides a convenient way for the locatetechnician to view and interact with facilities map information inreal-time while conducting a locate and/or marking operation (and/orimmediately before or after the marking operation).

In various aspects, the inventive concepts discussed herein generallyrelate to one of more of the following: 1) selection, from a local orremote library/archive, of one or more appropriate “base” facilitiesmaps or facilities map data sets relating to a given work site/dig area;2) manual or automated selection of an appropriate pan and/or zoom(resolution) for displaying, on a user interface/display of a markingdevice, facilities map information derived from the base facilitiesmap(s); 3) appropriately updating, if/as necessary, displayed facilitiesmap information while a marking device is used during a markingoperation; 4) overlaying, on the displayed facilities map information,marking information relating to the marking operation; and 5) storinglocally on the marking device, and/or transmitting from the markingdevice, facilities map information and/or overlaid marking information(e.g., for further processing, analysis and/or subsequent display).

Furthermore, in addition to facilities map information, it should beappreciated that the present disclosure contemplates other types ofimage information being accessed and displayed on a userinterface/display of a marking device to facilitate various aspects of alocate and/or marking operation. For example, other types of maps (e.g.,street/road maps, polygon maps, tax maps, etc.), architectural,construction and/or engineering drawings, land surveys, and photographicrenderings/images, and various information derived therefrom, includingvirtual white line (VWL) designations that delimit, on a map or otherimage, a planned excavation area, may be displayed on the marking deviceand may also be used as the basis for overlaying marking informationrelating to a marking operation.

I. MARKING DEVICE

One example of a marking device which may be configured to access, view,update, store, analyze and process facilities map information isdescribed below. It should be appreciated that the marking devicedescribed below is merely one example of a marking device that may beconfigured for applications involving facilities map information and/orother image information, and that the invention is not limited toimplementation on this marking device. In particular, other types ofmarking devices may be similarly configured as discussed herein, as wellas various types of locate devices and combined marking and locatedevices.

FIGS. 4 and 5 illustrate a functional block diagram and perspectiveview, respectively, of one example of a data acquisition system 100,including a marking device 110 and optionally a remote computer 150,according to one embodiment of the present invention. One or both of themarking device 110 and the remote computer 150 of the data acquisitionsystem 100 may be configured to sense one or more actuations of themarking device 110 (e.g., to dispense marking material during a markingoperation), and collect information based on one or more actuations ofthe marking device so as to generate an electronic record.

As shown in FIG. 4, in one embodiment marking device 110 includescontrol electronics 112, the components of which are powered by a powersource 114. Power source 114 may be any power source that is suitablefor use in a portable device, such as, but not limited to, one or morerechargeable batteries, one or more non-rechargeable batteries, a solarphotovoltaic panel, a standard AC power plug feeding an AC-to-DCconverter, and the like.

The marking device 110 is configured to hold a marking dispenser 116,which as shown in FIG. 5 is loaded into a marking material holder 140 ofthe marking device 110. In one exemplary implementation, the markingdispenser 116 is an aerosol paint canister that contains paint; however,it should be appreciated that the present invention is not limited inthis respect, as a marking material dispensed by the marking device 110may be any material, substance, compound, and/or element, used to mark,signify, and/or indicate. Examples of marking materials may include, butare not limited to, paint, chalk, dye, and/or marking powder.

As also shown in FIG. 4, in one embodiment control electronics 112 ofmarking device 110 may include, but are not limited to, a processor 118,at least a portion of an actuation system 120 (another portion of whichmay include one or more mechanical elements), a local memory 122, acommunication interface 124, a user interface 126, a timing system 128,and a location tracking system 130.

The processor 118 may be any general-purpose processor, controller, ormicrocontroller device. Local memory 122 may be any volatile ornon-volatile data storage device, such as, but not limited to, a randomaccess memory (RAM) device and a removable memory device (e.g., auniversal serial bus (USB) flash drive, a multimedia card (MMC), asecure digital card (SD), a compact flash card (CF), etc.). As discussedfurther below, the local memory may store a marking data algorithm 134,which may be a set of processor-executable instructions that whenexecuted by the processor 118 causes the processor to control variousother components of the marking device 110 so as to generate anelectronic record 135 of a marking operation, which record also may bestored in the local memory 122 and/or transmitted in essentiallyreal-time (as it is being generated) or after completion of a markingoperation to a remote device (e.g., remote computer 150). In otheraspects, the local memory 122 also may store a map or image viewerapplication 113 (hereafter simply “map viewer application”), and one ormore facilities maps or facilities map data sets 166 and/or other images168. As discussed further below, the one or more facilities maps/datasets 166 may in some implementations include a library of facilitiesmaps, or a database of facilities map data, for one or more differenttypes of facilities deployed in a geographical region.

In one exemplary implementation, a Linux-based processing system forembedded handheld and/or wireless devices may be employed in the markingdevice 110 to implement various components of the control electronics112. For example, the Fingertip4™ processing system, including a MarvellPXA270 processor and available from InHand Electronics, Inc.(www.inhandelectronics.com/products/fingertip4), may be used. Inaddition to the PXA270 processor (e.g., serving as the processor 118),the Fingertip4™ includes flash memory and SDRAM (e.g., serving as localmemory 122), multiple serial ports, a USB port, and other I/O interfaces(e.g., to facilitate interfacing with one or more input devices andother components of the marking device), supports a variety of wired andwireless interfaces (WiFi, Bluetooth, GPS, Ethernet, any IEEE 802.11interface, or any other suitable wireless interface) to facilitateimplementation of the communication interface 124, and connects to awide variety of LCD displays (to facilitate implementation of a userinterface/display). In yet other exemplary implementations, theprocessor 118 may be realized by multiple processors that divide/sharesome or all of the functionality discussed herein in connection with theprocessor 118. For example, in one implementation, an Atom™ processoravailable from Intel Corporation of Santa Clara, Calif., may be usedalone or in connection with one or more PIC processors to accomplishvarious functionality described herein.

Communication interface 124 of marking device 110 may be any wiredand/or wireless communication interface by which information may beexchanged between marking device 110 and an external or remote device,such as a remote computing device that is elsewhere in the dig area(i.e., not a part of the marking device 110) or outside the dig area.For example, data that is provided by components of data acquisitionsystem 100 and/or stored in local memory 122 (e.g., one or moreelectronic records 135, one or more facilities maps 166) may betransmitted via communication interface 124 to a remote computer, suchas remote computer 150, for processing. Similarly, one or morefacilities maps 166 may be received from the remote computer 150 or oneor more other external sources via the communication interface 124.Examples of wired communication interfaces may include, but are notlimited to, USB ports, RS232 connectors, RJ45 connectors, Ethernet, andany combination thereof. Examples of wireless communication interfacesmay include, but are not limited to, an Intranet connection, Internet,Bluetooth® technology, Wi-Fi, Wi-Max, IEEE 802.11 technology (e.g.,operating at a minimum bandwidth of 54 Mbps, or any other suitablebandwidth), radio frequency (RF), Infrared Data Association (IrDA)compatible protocols, Local Area Networks (LAN), Wide Area Networks(WAN), Shared Wireless Access Protocol (SWAP), any combination thereof,and other types of wireless networking protocols. The wireless interfacemay be capable of capturing signals that reflect a user's intent. Forexample, the wireless interface may include a microphone that cancapture a user's intent by capturing the user's audible commands.Alternatively, the wireless interface may interact with a device thatmonitors a condition of the user, such as eye movement, brain activity,and/or heart rate.

User interface 126 of marking device 110 may be any mechanism orcombination of mechanisms by which a user may operate data acquisitionsystem 100 and by which information that is generated by dataacquisition system 100 may be presented to the user. For example, userinterface 126 may include, but is not limited to, a display device(including integrated displays and external displays, such as Heads-UpDisplays (HUDs)), a touch screen, one or more manual pushbuttons, amicrophone to provide for audible commands, one or more light-emittingdiode (LED) indicators, one or more toggle switches, a keypad, an audiooutput (e.g., speaker, buzzer, and alarm), and any combination thereof.In one implementation, the user interface 126 includes a “menu/on”button to power up the marking device and provide a menu-drivengraphical user interface (GUI) displayed by the display device (e.g.,menu items and/or icons displayed on the display device) and navigatedby the technician via a joystick or a set of four “up/down/left/right”buttons, as well as a “select/ok” button to take some action pursuant tothe selection of a menu item/icon. As described below, the display mayalso be used in some embodiments of the invention to display informationrelating to one or more facilities maps and/or one or more other imagesgermane to a locate and/or marking information, as well as informationrelating to a placement of marking material in a dig area, a location ofan underground facility in a dig area, or any other suitable informationthat may be displayed based on information acquired to create anelectronic record 135.

In various embodiments, the one or more interfaces of the marking device110—including the communication interface 124 and user interface 126—maybe used as input devices to receive information to be stored in thememory 122, to facilitate various functions of the marking device and/orto be logged as part of an electronic record of a marking operation. Insome cases, marking information received via the interface(s) (e.g., viathe communication interface 124) may include ticket informationregarding underground facilities to be marked during a markingoperation. As another example, using an interface such as the userinterface 126, service-related information may be input, including anidentifier for the marking device used by the technician, an identifierfor a technician, and/or an identifier for the technician's employer.Alternatively, some or all of the service-related information similarlymay be received via the communication interface 124 (and likewise someor all of the ticket information may be received via the user interface126). As also noted above, facilities map information and/or other imageinformation also may be received via the communication interface 124.

The actuation system 120 of marking device 110 shown in the blockdiagram of FIG. 4 may include both electrical and mechanical elementsaccording to various embodiments discussed in further detail below, andfor purposes of illustration is shown in FIG. 4 as included as part ofthe control electronics 112. The actuation system 120 may include amechanical and/or electrical actuator mechanism (e.g., see the actuator142 shown in FIG. 5) to provide one or more signals or stimuli as aninput to the actuation system 120. Upon receiving one or more signals orstimuli (e.g., actuation/triggering by a locate technician or otheruser), the actuation system 120 causes marking material to be dispensedfrom marking dispenser 116. In various embodiments, the actuation system120 may employ any of a variety of mechanical and/or electricaltechniques (e.g., one or more switches or other circuit components, adedicated processor or the processor 118 executing instructions, one ormore mechanical elements, various types of transmitters and receivers,or any combination of the foregoing), as would be readily appreciated bythose of skill in the relevant arts, to cause the marking dispenser 116to dispense marking material in response to one or more signals orstimuli. The actuation system 120 also provides one or more outputsignals in the form of an actuation signal 121 to the processor 118 toindicate one or more actuations of the marking device, in response towhich the processor 118 may acquire/collect various marking informationand log data into the electronic record 135. Additional details ofexemplary actuation system implementations are provided below inconnection with FIGS. 5 through 7.

In some embodiments, the actuation system 120 may be configured so asnot to cause marking material to be dispensed from marking dispenser 116in response to one or more signals or stimuli; rather, the actuationsystem may merely facilitate a logging of data from one or more inputdevices in response to operation of an actuator/trigger, withoutnecessarily dispensing marking material. In some instances, this mayfacilitate “simulation” of a marking operation (i.e., simulating thedispensing of marking material) by providing an actuation signal 121 tothe processor 118 indicating one or more simulated actuation events, inresponse to which the processor may cause the logging of various datafor creating an electronic record without any marking material actuallybeing dispensed.

Location tracking system 130 of marking device 110 constitutes anothertype of input device that provides marking information, and may includeany device that can determine its geographical location to a certaindegree of accuracy. For example, location tracking system 130 mayinclude a global positioning system (GPS) receiver or a globalnavigation satellite system (GNSS) receiver. A GPS receiver may provide,for example, any standard format data stream, such as a National MarineElectronics Association (NMEA) data stream, or other data formats. Anerror correction component 131 may be, but is not limited to, anymechanism for improving the accuracy of the geographic informationprovided by location tracking system 130; for example, error correctioncomponent 131 may be an algorithm for correcting any offsets (e.g., dueto local disturbances in the atmosphere) in the geo-location data oflocation tracking system 130. While shown as part of a local locationtracking system of the marking device 110, error correction component131 alternatively may reside at a remote computing device, such asremote computer 150. In other embodiments, location tracking system 130may include any device or mechanism that may determine location by anyother means, such as performing triangulation by use of cellularradiotelephone towers.

In one exemplary implementation, the location tracking system 130 mayinclude an ISM300F2-05-V0005 GPS module available from Inventek Systems,LLC of Westford, Mass. (seewww.inventeksys.com/html/ism300f2-c5-v0005.html). The Inventek GPSmodule includes two UARTs (universal asynchronous receiver/transmitter)for communication with the processor 118, supports both the SIRF Binaryand NMEA-0183 protocols (depending on firmware selection), and has aninformation update rate of 5 Hz. A variety of geographic locationinformation may be requested by the processor 118 and provided by theGPS module to the processor 118 including, but not limited to, time(coordinated universal time—UTC), date, latitude, north/south indicator,longitude, east/west indicator, number and identification of satellitesused in the position solution, number and identification of GPSsatellites in view and their elevation, azimuth and SNR values, anddilution of precision values. Accordingly, it should be appreciated thatin some implementations the location tracking system 130 may provide awide variety of geographic information as well as timing information(e.g., one or more time stamps) to the processor 118.

In another embodiment, location tracking system 130 may not residelocally on marking device 110. Instead, location tracking system 130 mayreside on any on-site computer, which serves as a location referencepoint, to which the location of marking device 110 may be correlated byany other means, such as, but not limited to, by a triangulationtechnique between the on-site computer and marking device 110.

In some embodiments, control electronics 112 may also include one ormore of an electronic compass 160, an inclinometer 170, and one or moreaccelerometers 172. An inclinometer is an instrument for measuringangles of slope (or tilt) or inclination of an object with respect togravity. The inclinometer 170 may be any commercially availableinclinometer device. In one example, inclinometer 170 may be a digitaldevice for sensing the inclination of the marking device 110 in which itis installed (i.e., senses angle of spray). An accelerometer is a devicefor measuring acceleration and gravity-induced reaction forces. Amulti-axis accelerometer is able to detect magnitude and direction ofthe acceleration as a vector quantity. The acceleration specificationmay be in terms of g-force, which is a measurement of an object'sacceleration. The accelerometer 172 may be any commercially availableaccelerometer device, including, for example, Part No. ADXL330 sold byAnalog Devices of Wilmington, Mass. In one example, accelerometer 172may be used for detecting the rate of movement of the marking device 110in which it is installed. Electronic compass 160 may be any commerciallyavailable electronic compass, including, for example, the OS5000-S soldby OceanServer Technology, Inc. of Fall River, Mass., the SP3002D soldby SPARTON Corporation of Brooksville, Fla., the PNI-PRIME sold by PNISensor Corp. of Santa Rosa, Calif., the Revolution GS sold by True NorthLLC of Maynard, Mass., or the HMR3400 sold by Honeywell International,Inc. of Morristown, N.J.

With respect to other input devices of the marking device 110 that mayprovide marking information, the control electronics 112 may alsoinclude a timing system 128 having an internal clock (not shown), suchas a crystal oscillator device, for processor 118. Additionally, timingsystem 128 may include a mechanism for registering time with a certaindegree of accuracy (e.g., accuracy to the minute, second, ormillisecond) and may also include a mechanism for registering thecalendar date. In various implementations, the timing system 128 may becapable of registering the time and date using its internal clock, oralternatively timing system 128 may receive its time and dateinformation from the location tracking system 130 (e.g., a GPS system)or from an external timing system, such as a remote computer or network,via communication interface 124. In yet other implementations, adedicated timing system for providing timing information to be logged inan electronic record 135 may be optional, and timing information forlogging into an electronic record may be obtained from the locationtracking system 130 (e.g., GPS latitude and longitude coordinates with acorresponding time stamp). Timing information may include, but is notlimited to, a period of time, timestamp information, date, and/orelapsed time.

Marking material detection mechanism 132 of the marking device 110 shownin FIG. 4 is another type of input device that provides markinginformation, and may be any mechanism or mechanisms for determining apresence or absence of a marking dispenser 116 in or otherwise coupledto the marking device 110, as well as determining certainattributes/characteristics of the marking material within markingdispenser 116 when the dispenser is placed in or coupled to the markingdevice. As shown in FIG. 5, in some embodiments the marking materialdetection mechanism 132 may be disposed generally in an area proximateto a marking material holder 140 in which a marking dispenser 116 may beplaced.

For example, in one embodiment, the marking material detection mechanism132 may include one or more switch devices (e.g., a make/break singlepole/single throw contact switch) disposed at one or more points alongthe marking material holder 140 and electrically coupled to theprocessor 118. The switch device(s) may also be coupled to ground or aDC supply voltage, such that when the switch device is in a first state(e.g., closed/making contact) the ground or DC supply voltage is passedto the processor 118 (e.g., via an I/O pin of the processor whichprovides an interrupt to, or is periodically monitored by, theprocessor), and when the switch is in a second state (e.g., open/nocontact) the ground or DC supply voltage is not passed to the processor118. When the marking dispenser 116 is present in the holder 140, theswitch device(s) is in one of two possible states and when there is nomarking dispenser the switch device(s) is in another of the two possiblestates (e.g., the marking dispenser, when present, may depress theswitch device(s) so as to make contact and pass the ground/DC voltage tothe processor). In this manner, the marking material detection mechanism132 may provide a signal to the processor indicating the presence orabsence of the marking dispenser 116 in the marking device 110.

The marking material detection mechanism 132 also or alternatively mayinclude a barcode reader to read barcode data from a dispenser 116and/or a radio-frequency identification (RFID) reader for readinginformation from an RFID tag that is provided on marking dispenser 116.The RFID tag may include, for example, a unique serial number oruniversal product code (UPC) that corresponds to the brand and/or typeof marking material in marking dispenser 116. The type of informationthat may be encoded within the RFID tag on marking dispenser 116 mayinclude product-specific information for the marking material, but anyinformation of interest may be stored on an RFID tag. For example,user-specific information and/or inventory-related information may bestored on each RFID tag for a marking dispenser 116 to facilitateinventory tracking of marking materials. In particular, an identifierfor a technician may be stored on an RFID tag when the technician isprovided with a marking dispenser 116, and information relating toweight, amount dispensed, and/or amount remaining may be written to theRFID tag whenever the marking dispenser is used.

In one exemplary implementation, the marking material detectionmechanism 132 may include a Micro RWD MIFARE-ICODE RFID reader moduleavailable from IB Technology (Eccel Technology Ltd) of Aylesbury,Buckinghamshire, UK (see www.ibtechnology.co.uk/products/icode.htm). TheMicro RWD reader module includes an RS232 communication interface tofacilitate communication between the processor 118 and the reader module(e.g., via messages sent as a string of ASCII characters), and supportsboth reading information from an RFID tag attached to a markingdispenser as well as writing information to an RFID tag attached to themarking dispenser. In one aspect of an exemplary implementation, anantenna constituted by one or more turns of wire (e.g., two turns of awg26 wire, 6.5 cm in diameter, about 1 uH) is coupled to the Micro RWDreader module and disposed in the marking material holder 140 of themarking device 110 (see FIG. 5), proximate to a marking dispenser 116when placed in the holder 140, so as to capture close near field signals(e.g., from an RFID tag on the dispenser, within about 2 inches) andexclude far field signals. In another aspect, the Micro RWD readermodule may be configured to read RFID tags having an ICODE SLI format(e.g., ISO 15693 ICODE SLI). In yet another aspect, an RFID tag may beaffixed to an aerosol paint can serving as the marking dispenser, suchthat the tag conforms to a plastic cap of the paint can and is disposedat a particular location relative to a notch in the cap (e.g., 90degrees+/−15 degrees from the notch) that allows access to the spraynozzle of the can and is in a relatively predictable positionsubstantially aligned with the antenna when the paint can is placed inthe marking material holder 140. Examples of RFID tags suitable for thispurpose are available from BCS Solutions, Inc. (seewww.bcssolutions.com/solutions/rfid) and include, but are not limitedto, the HF Bullseye Wet Inlay SLA Round 40.

In yet other embodiments, marking material detection mechanism 132 mayalternatively or further be configured to detect properties of markingmaterial as it is dispensed. For example, the marking material detectionmechanism may include one or more of an optical sensor, an olfactorysensor, an auditory sensor (e.g., a microphone), a weight sensor, andany combination thereof. For example, in one embodiment an opticalsensor in the marking device may be used to identify the compositionand/or type of marking material in the marking dispenser by analyzinglight reflected by the material as it is dispensed. Similarly, anolfactory sensor may be used to identify one or more characteristics ofthe marking material based on an odor profile of the material, and anauditory sensor may be used to identify the difference between paintbeing sprayed from an aerosol can and aerosol without paint beingsprayed from a can (e.g., as the dispenser becomes emptied of paint).

In one embodiment, information provided by one or more input devices ofthe marking device 110 (e.g., the timing system 128, the locationtracking system 130, the marking material detection mechanism 132, theuser interface 126, the communication interface 124) is acquired andlogged (stored in memory) upon actuation of the actuation system 120(e.g., triggering an actuator). Some embodiments of the invention mayadditionally or alternatively acquire/log information from one or moreinput devices at one or more times during or throughout an actuation,such as when a technician is holding a mechanical or electrical actuatorfor some period of time and moving to dispense marking material in aline. In various aspects of such embodiments, marking informationderived from one or more input devices may be collected at a start timeof an actuation, at one or more times during an actuation, and in somecases at regular intervals during an actuation (e.g., several times persecond, once per second, once every few seconds). Further, some markinginformation may be collected at an end of an actuation, such as timeinformation that may indicate a duration of an actuation.

Additionally, it should be appreciated that while some markinginformation may be received via one or more input devices at the startof each marking operation and upon successive actuations of the markingdevice, in other cases some marking information, as well as facilitiesmaps information and/or other image information, may be collected by orprovided to the marking device prior to a marking operation (e.g., onpower-up or reset of the marking device, as part of an electronicinstruction or dispatch by a locate company, and/or in response to arequest/query from a locate technician), and stored in local memory 122for subsequent use by the marking device (e.g., display of informationvia the user interface display 146, later incorporation into anelectronic record, etc.). For example, prior to a given markingoperation and one or more actuations of the marking device, one or moreof ticket information, service-related information, facilities mapsinformation, and other image information, may have already been received(e.g., via the communication interface 124 and/or user interface 126)and stored in local memory 122. Pursuant to a marking operation (e.g.,immediately before, during and/or after a marking operation),information previously received via the interface(s) may be retrievedfrom the local memory (if stored there initially), and displayed and/orentered into an electronic record as appropriate, in some case togetherwith information collected pursuant to one or more actuations of themarking device. In some implementations, ticket information and/orservice-related information may be received via the interface(s) andstored in an entry in the electronic record 135 “directly” in responseto one or more actuations of the marking device (e.g., without beingfirst stored in local memory).

In sum, according to embodiments of the present invention, variousmarking information from one or more input devices, as well asfacilities map information and/or other image information, regardless ofhow or when it is received, may be displayed in various manners and/orstored in memory of the marking device (e.g., in an electronic record ofa marking operation), and in some implementations at least some of themarking information may be logged pursuant to one or more actuations ofthe marking device.

In various implementations, the optional remoter computer 150 of thedata acquisition system 100 may be any external computer system withwhich the marking device 110 communicates (e.g., via the communicationsinterface 124). In one embodiment, the remote computer 150 may be acentralized computer, such as a central server of an undergroundfacility locate service provider. In another embodiment, remote computer150 may be a computer that is at or near the work site (i.e.,“on-site”), e.g., a computer that is present in a locate technician'svehicle. As shown in FIGS. 4 and 5, the remote computer may also oralternatively store one or more of the marking data algorithm 134, themap viewer application 113, one or more facilities maps 166 (e.g., alibrary/archive of facilities maps), and one or more images 168. To thisend, in some exemplary implementations, an example of a remote computer150 may include an image server or a facilities maps server to providefacilities maps/images to the marking device 110.

Whether resident and/or executed on either the marking device 110 or theremote computer 150, as noted above the marking data algorithm 134includes a set of processor-executable instructions (e.g., stored inmemory, such as local memory 122 of the marking device) that, whenexecuted by processor 118 of the marking device 110 or anotherprocessor, processes information (e.g., various marking information)collected in response to (e.g., during) one or more actuations of themarking device 110, and/or in some cases before or after a givenactuation or series of actuations. As also discussed above, according tovarious embodiments the actuations of marking device 110 may effect bothdispensing marking material and logging of marking information, ormerely logging of marking information for other purposes (e.g.,simulating the dispensing of marking material) without dispensingmarking material. In either situation, marking data algorithm 134, whenexecuted by the processor 118, may cause the processor to performcollection, logging/storage (creation of electronic records), and insome instances further processing and analysis of various markinginformation with respect to marking device actuations.

While the functionality of various components of the marking device 110was discussed above in connection with FIG. 4, FIG. 5 shows somestructural aspects of the marking device 110 according to oneembodiment. For example, the marking device 110 may include an elongatedhousing 136 in which is disposed one or more elements of the actuationsystem 120, one or more elements of the control electronics 112 and thepower source 114. Elongated housing 136 may be hollow or may containcertain cavities or molded compartments for installing any componentstherein, such as the various components of marking device 110 that areshown in FIG. 4. The elongated housing 136 and other structural elementsassociated with the housing, as discussed below, may be formed of anyrigid, semi-rigid, strong, and lightweight material, such as, but notlimited to, molded plastic and aluminum.

Incorporated at a proximal end of elongated housing 136 may be a handle138, which provides a convenient grip by which the user (e.g., thelocate technician) may carry the marking device 110 during use (i.e.,the exemplary marking device depicted in FIG. 5 is intended to be ahand-held device). In one implementation, the power source 114 may beprovided in the form of a removable battery pack housing one or morerechargeable batteries that are connected in series or parallel in orderto provide a DC voltage to marking device 110, and disposed within acompartment in the handle 138. Such an arrangement facilitates use ofconventional removable/rechargeable battery packs often employed in avariety of cordless power tools, in which the battery pack similarly issituated in a handle of the tool. It should be appreciated, however,that the power source 114 in the form of a battery pack may be disposedin any of a variety of locations within or coupled to the elongatedhousing 136.

As also shown in FIG. 5, mounted near handle 138 is user interface 126,which may include a display 146. The display 146 may be a touch screendisplay to facilitate interaction with a user/technician, and/or theuser interface also may include one or more buttons, switches,joysticks, a keyboard, and the like to facilitate entry of informationby a user/technician. One or more elements of the control electronics112 (e.g., the processor 118, memory 122, communication interface 124,and timing system 128) also may be located in the proximal end of theelongated housing in the vicinity of the user interface 126 and display146. As with the power source 114, it should be appreciated that one ormore elements of the control electronics 112 may be disposed in any of avariety of locations within or coupled to the elongated housing 136.

In the embodiment of FIG. 5, the location tracking system 130 similarlymay be positioned on the proximal end of the elongated housing 136 tofacilitate substantially unobstructed exposure to the atmosphere; inparticular, as illustrated in FIG. 5, the location tracking system 130may be situated on an a ground plane 133 (providing an electrical groundat least at the antenna frequency of the location tracking system, e.g.,at approximately 1.5 GHz) that extends from the proximal end of thehousing 136 and is approximately parallel to the ground, surface orpavement when the marking device is being normally operated by atechnician (so as to reduce signal modulation with subtle movements ofthe marking device).

As also shown in FIG. 5, incorporated at the distal end of elongatedhousing 136 is a marking dispenser holder 140 for holding one or moremarking dispensers 116 (e.g., an aerosol paint canister). Dispenser 116may be one or more replaceable dispensers or one or more reusablerefillable dispensers (including a fixed reservoir forming a part of thedevice 110) or any other suitable dispenser. Also situated at the distalend of the housing is the marking material detection mechanism 132 todetect a presence or absence of the marking dispenser 116 in the markingmaterial holder 140, and/or one or more characteristics of the markingmaterial 148, as well as an actuation mechanism 158, which in someimplementations may constitute part of the actuation system 120 and beemployed to interact with the marking dispenser 116 so as to effectdispensing of the marking material 148.

With respect to the actuation system 120, as shown in FIG. 5, at least aportion of the actuation system 120 is indicated generally along thelength of the elongated housing for purposes of illustration. Morespecifically, however, in various implementations the actuation system120 may include multiple components disposed in various places in, on orcoupled to the marking device 110. For example, in the embodiment ofFIG. 5, the actuation system 120 includes an actuator 142, which forexample may be a mechanical mechanism provided at the handle 138 in theform of a trigger that is pulled by a finger or hand of anuser/technician. The actuation system 120 further includes the actuationmechanism 158 disposed at the distal end of the marking device that isresponsive to the actuator 142 to dispense marking material. In general,in various exemplary implementations as discussed in further detailbelow, the actuation system 120 may employ any of a variety ofmechanical and/or electrical techniques to cause the marking dispenser116 to dispense marking material 148 in response to one or more signalsor stimuli. In the embodiment shown in FIG. 5, the signal/stimulus isinitially provided to the actuation system via the mechanical actuator142; i.e., a locate technician or other user triggers (e.g.,pulls/depresses) the actuator 142 to provide a signal/stimulus to theactuation system 120, which in turn operates the actuation mechanism 158to dispense marking material in response to the signal/stimulus.

In response to the signal/stimulus provided by the actuator 142, asdiscussed above the actuation system may also provide an actuationsignal 121 to the processor 118 to indicate an actuation. As discussedin further detail below in connection with FIG. 15, pursuant to theexecution by the processor 118 of the marking data algorithm 134, theactuation signal 121 may be used to cause the logging of informationthat is provided by one or more components of the marking device 110 soas to generate an electronic record of the marking operation.

FIGS. 6A and 6B illustrate a portion of the actuation system 120according to one embodiment of the present invention. FIG. 6A shows theactuator 142 in an un-actuated state, whereas FIG. 6B shows the actuator142 in an actuated state (in which a signal/stimulus is provided by theactuator). In the example of FIGS. 6A and 6B, the actuator 142 iscoupled to a mechanical coupler 152 which extends along a length of theelongated housing and is in turn coupled to a mechanical actuationmechanism 158 at the distal end of the housing (not shown in FIGS. 6Aand 6B) that ultimately effects dispensing of marking material when theactuator is in the actuated state. The portion of the actuation system120 shown in FIGS. 6A and 6B also includes a sensor 160 which isconfigured to provide an actuation signal 121 to the processor 118 toindicate one or both of the respective actuated and un-actuated statesof the actuator 142.

In one implementation, the sensor 160 may include a switch device (e.g.,a make/break single pole/single throw contact switch) disposed along thehandle 138 of the marking device such that, when pulled, the actuatorcontacts (e.g., depresses) the switch causing a state of the switch totoggle. In another implementation, the sensor 160 may include a switchdevice such as a reed (magnetic) switch disposed at some point along thelength of the elongated housing; in such an implementation, themechanical coupler 152 may have a magnet disposed along it at anappropriate position relative to the reed switch, such that movement ofthe mechanical coupler 152 upon actuation of the actuator 142 causes astate of the reed switch to toggle. Electrically, a switch deviceserving as the sensor 160 may be coupled to ground or a DC supplyvoltage, such that when the switch device is in a first state (e.g.,closed/making contact) the ground or DC supply voltage is passed to theprocessor 118 (e.g., via an I/O pin of the processor which provides aninterrupt to, or is periodically monitored by, the processor), and whenthe switch is in a second state (e.g., open/no contact) the ground or DCsupply voltage is not passed to the processor 118. In this manner, thesensor 160 may provide the actuation signal 121 to the processorindicating actuation (and release) of the actuator 142.

FIG. 7 illustrates various components of an actuation system 120according to other embodiments of the present invention. Generallyspeaking, the actuation system 120 may include the actuator 142 and thesensor 160 to detect actuation and release of the actuator 142 (and alsoprovide a corresponding actuation signal 121 representing same to theprocessor 118). While a “trigger-pull” type of actuator 142 is shownprimarily for purposes of illustration in FIG. 5, it should beappreciated that more generally an actuator of the actuation system 120may be implemented by any form or combination of a lever, switch,program, processor, screen, microphone for capturing audible commands,and the like, as discussed above. For example, in one implementation, amicrophone may serve as both the actuator 142 and the sensor 160 shownin FIG. 7 to provide an actuation signal 121 based on audible commands,so as to effect voice-activated actuation of the marking device.

FIG. 7 also shows that the actuation system 120 of this embodimentincludes a link transmitter 168 coupled and responsive to the sensor 160to transmit one or more signals and/or other stimulus via an actuationlink 164, and a link receiver 162 to receive the one or more signalsand/or other stimulus from the actuation link 164. In response to suchsignals and/or other stimulus, the link receiver 162 operates theactuation mechanism 158. The link transmitter 168, the link 164, and thelink receiver 162 may include one or more electrical and/or mechanicalcomponents. For example, the link receiver 162 may include a linearsolenoid mechanically coupled to the actuation mechanism 158 and whosemovement is responsive to one or more signals and/or stimuli receivedfrom the link 164. In various exemplary implementations, the linktransmitter 168 and the link 164 simply may include a wire that couplesthe sensor 160 to the solenoid to activate the solenoid upon changes ofstate in the actuation signal 121. Alternatively, the transmitter 168may be an RF transmitter that is activated in response to the actuationsignal 121, the link 164 may be a wireless link, and the receiver 162may include an RF receiver.

Other examples of transmitter/link/receiver combinations include, butare not limited to, an acoustic transmitter/link/receiver (e.g., a soundwave source that provides a sound wave of a certain tone, duration,and/or amplitude when the actuator is actuated, and a correspondingsound wave detector), an optical transmitter/link/receiver (e.g., alight or laser source that provides an optical signal of a certainwavelength, duration, and/or amplitude when the actuator is actuated,and a corresponding optical detector), a fluid transmitter/link/receiver(e.g., a fluid system that provides a fluid control output of a certainvolume, pressure, and/or duration when the actuator is actuated, and acorresponding fluid sensor for sensing the presence of, for example, ashort blast of water of a certain volume, pressure, and/or duration toindicate an actuation; the fluid system may be, for example, aclosed-loop system that has a source reservoir at the top of the markingdevice, a fluid line in proximity with the fluid sensor, a returnreservoir for capturing water during the actuation process, andappropriate pressure regulation and ducts for cycling water from thereturn reservoir back to the source reservoir), and an airtransmitter/link/receiver (e.g., an air system that provides an aircontrol output of a certain volume, pressure, and/or duration when theactuator is actuated, and a corresponding air sensor for sensing thepresence of, for example, a blast or puff of air of a certain volume,pressure, and/or duration to indicate an actuation).

While not explicitly shown in FIG. 7, in yet other embodiments it shouldbe appreciated that the sensor 160 may be coupled to the processor 118(to provide the actuation signal 121 representing actuation/release ofthe actuator), and in turn the processor may provide a signal to thelink transmitter 168, such that dispensing of marking material may inpart be under the control of the processor 118 executing particularinstructions for this purpose. More specifically, while in someimplementations dispensing of marking material may be directlyresponsive to actuation of the actuator (and cease upon release of theactuator), in other implementations dispensing of marking material maybe initiated in some manner upon actuation of the actuator, but thencontinued dispensing of marking material may not necessarily be dictatedby continued actuation, or release, of the actuator. Rather, theprocessor 118 may provide one or more signals or commands to the linktransmitter 168 to govern dispensing of marking material in some mannerthat does not necessarily track each actuation and release of theactuator.

II. FACILITIES MAPS

As noted above and discussed in further detail below, variousembodiments of the present invention relate to accessing and displayingfacilities map information. A facilities map is any physical,electronic, or other representation of the geographic location, type,number, and/or other attributes of a facility or facilities. Facilitiesmaps may be supplied by various facility owners and may indicate thegeographic location of the facility lines (e.g., pipes, cables, and thelike) owned and/or operated by the facility owner. For example,facilities maps may be supplied by the owner of the gas facilities,power facilities, telecommunications facilities, water and sewerfacilities, and so on.

As indicated above, facilities maps may be provided in any of a varietyof different formats. As facilities maps often are provided by facilityowners of a given type of facility, typically a set of facilities mapsincludes a group of maps covering a particular geographic region anddirected to showing a particular type of facility disposed/deployedthroughout the geographic region. One facilities map of such a set ofmaps is sometimes referred to in the relevant arts as a “plat.”

Perhaps the simplest form of facilities maps is a set of paper maps thatcover a particular geographic region. In addition, some facilities mapsmay be provided in electronic form. An electronic facilities map may insome instances simply be an electronic conversion (i.e., a scan) of apaper facilities map that includes no other information (e.g.,electronic information) describing the content of the map, other thanwhat is printed on the paper maps.

Alternatively, however, more sophisticated facilities maps also areavailable which include a variety of electronic information, includinggeographic information and other detailed information, regarding thecontents of various features included in the maps. In particular,facilities maps may be formatted as geographic information system (GIS)map data, in which map features (e.g., facility lines and otherfeatures) are represented as shapes and/or lines, and the metadata thatdescribes the geographic locations and types of map features isassociated with the map features. In some examples, a GIS map data mayindicate a facility line using a straight line (or series of straightlines), and may include some symbol or other annotation (e.g., a diamondshape) at each endpoint of the line to indicate where the line beginsand terminates. From the foregoing, it should be appreciated that insome instances in which the geo-locations of two termination orend-points of a given facility line may be provided by the map, thegeo-location of any point on the facility line may be determined fromthese two end-points.

Examples of a wide variety of environmental landmarks and other featuresthat may be represented in GIS facilities map data include, but are notlimited to: landmarks relating to facilities such as pedestal boxes,utility poles, fire hydrants, manhole covers and the like; one or morearchitectural elements (e.g., buildings); and/or one or more trafficinfrastructure elements (e.g., streets, intersections, curbs, ramps,bridges, tunnels, etc.). GIS facilities map data may also includevarious shapes or symbols indicating different environmental landmarksrelating to facilities, architectural elements, and/or trafficinfrastructure elements.

Examples of information provided by metadata include, but are notlimited to, information about the geo-location of various points along agiven line, the termination points of a given line (e.g., the diamondshapes indicating the start and end of the line), the type of facilityline (e.g., facility type and whether the line is a service line ormain), geo-location of various shapes and/or symbols for other featuresrepresented in the map (environmental landmarks relating to facilities,architectural elements, and/or traffic infrastructure elements), andtype information relating to shapes and/or symbols for such otherfeatures.

The GIS map data and metadata may be stored in any of a variety of ways.For example, in some embodiments, the GIS map data and metadata may beorganized into files, where each file includes the map data and metadatafor a particular geographic region. In other embodiments, the GIS mapdata and metadata may be stored in database and may be indexed in thedatabase by the geographical region to which the map data and metadatacorresponds.

Facilities maps may include additional information that may be useful tofacilitate a locate and/or marking operation. For example, variousinformation that may be included in a legend of the facilities map, orotherwise associated with the facilities map (e.g., included in themetadata or otherwise represented on the map), may include, but is notlimited to, a date of the facilities map (e.g., when the map was firstgenerated/created, and/or additional dates corresponding toupdates/revisions), a number of revisions to the facilities map (e.g.,revision number, which may in some instances be associated with a date),one or more identifiers for a source, creator, owner and/or custodian ofthe facilities map (e.g., the owner of the facility type represented inthe map), various text information (e.g., annotations to update one ormore aspects or elements of the map), and any other legend informationthat may be included or represented in the map.

For facilities maps in electronic form, a variety of digital formats offacilities maps may be used including, but not limited to, a vectorimage format that is the typical output format of computer-aided design(CAD) tools. In one example, some facilities maps may be in a DWG(“drawing”) format, which is a format that used for storing two andthree dimensional design data and metadata, and is a native used byseveral CAD packages including AutoCAD, Intellicad, and PowerCAD.However, those skilled in the art will recognize that facilities mapsmay be in any of several vector and/or raster image formats, such as,but not limited to, DWG, DWF, DGN, PDF, TIFF, MFI, PMF, and JPG.

As noted above, in some instances in which facilities maps are in avector image format, a certain line on the facilities map may berepresented by a starting point geo-location, an ending pointgeo-location, and metadata about the line (e.g., type of line, depth ofline, width of line, distance of line from a reference point (i.e.,tie-down), overhead, underground, line specifications, etc.). Accordingto one embodiment of the present invention as discussed in greaterdetail below, to facilitate display of facilities map informationrelating to multiple different types of facilities, each vector imagemay be assembled in layers, in which respective layers correspond, forexample, to different types of facilities (e.g., gas, water, electric,telecommunications, etc.). In one aspect of such an embodiment, eachlayer is, for example, a set of vector images that are grouped togetherin order to render the representation of the certain type of facility.

FIG. 8 shows an example of a visual representation of a portion of anelectronic facilities map 600. In this example, facilities map 600 is atelecommunications facilities map that is supplied by atelecommunications company. Facilities map 600 shows telecommunicationsfacilities in relation to certain landmarks, such as streets and roads,using lines and shapes. As discussed above, the electronic facilitiesmap may include metadata indicating what various lines, symbols and/orshapes represent, and indicating the geo-location of these lines,symbols and/or shapes. With respect to exemplary environmental landmarksand other features, facilities map 600 may include both visualinformation (graphics and text) and metadata relating to utility poles602, manhole 604, streets 606, and any of a variety of other landmarksand features that may fall within the geographic area covered by thefacilities map 600.

III. OTHER TYPES OF IMAGE INFORMATION

As also noted above and discussed in further detail below, variousembodiments of the present invention relate to accessing and displayingnot only facilities map information but other types of image informationas well and, as with facilities map information, different images can beselected for viewing on the marking device at different times, accordingto various criteria. In some exemplary implementations, an “input image”may be stored in local memory 122 of the marking device and/or retrievedfrom the optional remote computer 150 (e.g., via the communicationinterface 124) and then stored in local memory, accessed, and variousinformation may be derived therefrom for display (e.g., all or a portionof the input image, metadata associated with the input image, etc.).

For purposes of the present application, an input image is any imagerepresented by source data that is electronically processed (e.g., thesource data is in a computer-readable format) to display the image on adisplay device. An input image may include any of a variety ofpaper/tangible image sources that are scanned (e.g., via an electronicscanner) or otherwise converted so as to create source data (e.g., invarious formats such as XML, PDF, JPG, BMP, etc.) that can be processedto display the input image, including scans of paper facilities maps. Aninput image also may include an image that originates as source data oran electronic file without necessarily having a correspondingpaper/tangible copy of the image (e.g., an image of a “real-world” sceneacquired by a digital still frame or video camera or other imageacquisition device, in which the source data, at least in part,represents pixel information from the image acquisition device).

In some exemplary implementations, input images may be created,provided, and/or processed by a geographic information system (GIS) thatcaptures, stores, analyzes, manages and presents data referring to (orlinked to) location, such that the source data representing the inputimage includes pixel information from an image acquisition device(corresponding to an acquired “real world” scene or representationthereof), and/or spatial/geographic information (“geo-encodedinformation”).

In view of the foregoing, various examples of input images and sourcedata representing input images, to which the inventive conceptsdisclosed herein may be applied, include but are not limited to:

-   -   Manual “free-hand” paper sketches of the geographic area (which        may include one or more buildings, natural or man-made        landmarks, property boundaries, streets/intersections, public        works or facilities such as street lighting, signage, fire        hydrants, mail boxes, parking meters, etc.);    -   Various maps indicating surface features and/or extents of        geographical areas, such as street/road maps, topographical        maps, military maps, parcel maps, tax maps, town and county        planning maps, call-center and/or facility polygon maps, virtual        maps, etc. (such maps may or may not include geo-encoded        information);    -   Architectural, construction and/or engineering drawings and        virtual renditions of a space/geographic area (including “as        built” or post-construction drawings);    -   Land surveys, i.e., plots produced at ground level using        references to known points such as the center line of a street        to plot the metes and bounds and related location data regarding        a building, parcel, utility, roadway, or other object or        installation;    -   A grid (a pattern of horizontal and vertical lines used as a        reference) to provide representational geographic information        (which may be used “as is” for an input image or as an overlay        for an acquired “real world” scene, drawing, map, etc.);    -   “Bare” data representing geo-encoded information (geographical        data points) and not necessarily derived from an        acquired/captured real-world scene (e.g., not pixel information        from a digital camera or other digital image acquisition        device). Such “bare” data may be nonetheless used to construct a        displayed input image, and may be in any of a variety of        computer-readable formats, including XML); and    -   Photographic renderings/images, including street level,        topographical, satellite, and aerial photographic        renderings/images, any of which may be updated periodically to        capture changes in a given geographic area over time (e.g.,        seasonal changes such as foliage density, which may variably        impact the ability to see some aspects of the image).

It should also be appreciated that source data representing an inputimage may be compiled from multiple data/information sources; forexample, any two or more of the examples provided above for input imagesand source data representing input images, or any two or more other datasources, can provide information that can be combined or integrated toform source data that is electronically processed to display an image ona display device.

Various examples of input images as discussed above are provided inFIGS. 9-14. For example, FIG. 9 shows a sketch 1000, representing anexemplary input image; FIG. 10 shows a map 1100, representing anexemplary input image; FIG. 11 shows a construction/engineering drawing1300, representing an exemplary input image; FIG. 12 shows a land surveymap 1400, representing an exemplary input image; FIG. 13 shows a grid1500, overlaid on the construction/engineering drawing 1300 of FIG. 11,representing an exemplary input image; and FIG. 14 shows a street levelimage 1600, representing an exemplary input image.

IV. DISPLAYING FACILITIES MAP INFORMATION AND/OR OTHER IMAGE INFORMATIONON A MARKING DEVICE

In some embodiments, marking device 110 may display various informationrelating to one or more facilities maps or one or more input images ondisplay 146. For example, processor(s) 118 may access facilities mapdata (e.g., from a file or a database) stored in local memory 122 or mayretrieve facilities map data stored on remote computer 150 and maydisplay on display 146 facilities maps based on the facilities map data.

In some embodiments, processor 118 may execute a map viewer application113 for displaying facilities maps and/or input images. The map viewerapplication 113 may be a custom application or any conventional viewerapplication that is capable of reading in electronic facilities mapsdata or other input images, and rendering all or a portion of theelectronic facilities maps data/input images to an image that can beviewed on display 146. Examples of conventional map viewer applicationssuitable for purposes of some embodiments of the present inventioninclude, but are not limited to, the Bentley® viewer application fromBentley Systems, Inc. (Exton, Pa.) and the ArcGIS viewer applicationfrom Environmental Systems Research Institute (Redlands, Calif.). Whilethe discussion below initially focuses on the display of facilities mapinformation for purposes of illustrating some of the inventive conceptsdisclosed herein, it should be appreciated that the various conceptsdiscussed below apply generally to the display of other types of imageinformation as well.

Processor 118 may select a map to be displayed on display 146 in any ofvariety of ways. In some embodiments, a technician using the markingdevice may manually select a map to be displayed. For example, thetechnician may access a list of facilities maps available in localmemory 122 and/or stored on remote computer using user interface 126(e.g., via a menu-driven graphics user interface on the user interface126) and may select a desired map from the list. In response, processor118 may access the corresponding map data and render an image of the mapor a portion of the map on display 146 (e.g., using the map viewerapplication 113). The technician may then also adjust the particularportion of the map that is displayed on display 146 by using userinterface 146 to pan or scroll to the desired portion of the map, andmay additionally select the desired zoom level at which the portion ofthe map is displayed.

In some embodiments, processor 118, in addition to or instead ofproviding the capability for a user/technician to manually selectfacilities map information to be displayed on display 146, may alsoautomatically select a facilities map and display all or a portion ofthe selected facilities map on display 146. A variety of techniques maybe used to automatically select a facilities map to be displayed ondisplay 146, as well as a default pan and/or zoom for the selected map,and the invention is not limited to any particular technique.

In some embodiments, a facilities map may be automatically selected fordisplay based, at least in part, on the type of facility being marked bythe marking device and/or the current location of the marking device(e.g., obtained from the location tracking system).

For example, in some embodiments, processor 118 may determine the typeof facility being marked by the marking device (e.g., using markingmaterial detection mechanism 132) and select a facilities map based onthat facility type. As discussed above, marking material detectionmechanism may determine the type of facility being marked by determiningthe color of the marking material loaded into and/or being dispensed bythe marking device. Because each marking material color corresponds to aparticular type of facility, the color of the marking material may beused to select a facilities map. Table 1 shows an example of thecorrespondence of marking material color to the type of facility to bemarked.

TABLE 1 Correspondence of color to facility type Marking material colorFacility Type Red Electric power lines, cables or conduits, and lightingcables Yellow Gas, oil, steam, petroleum, or other hazardous liquid orgaseous materials Orange Communications, cable TV, alarm or signallines, cables, or conduits Blue Water, irrigation, and slurry linesGreen Sewers, storm sewer facilities, or other drain lines WhiteProposed excavation Pink Temporary survey markings Purple Reclaimedwater, irrigation and slurry lines Black Mark-out for errant lines

Thus, for example, if processor 118 determines from marking materialdetection mechanism that the color of the marking material loaded intoand/or being dispensed by the marking device is red, then electric powerlines may be determined as the type of facility being marked. As anotherexample, if processor 118 determines from marking material detectionmechanism that the color of the marking material loaded into and/orbeing dispensed by the marking device is yellow, then gas lines may bedetermined as the type of facility being marked.

In some embodiments, rather than determine the type of facility beingmarked based on the color of the marking material, processor 118 mayprompt, via user interface 126, the technician using the marking deviceto manually input the type of facility being marked, and may accept thetechnician's input as the type of facility being marked. In yet anotherembodiment, facility type information may be derived from the ticketinformation, discussed above in section I; in particular, ticketinformation typically includes one or more member codes representingfacility owners of different types of facilities, and available ticketinformation may be parsed to determine relevant facility types based onone or more member codes present in the ticket information. Accordingly,in some implementations, one or more appropriate facilities maps may beselected, before the marking operation and independently of the markingmaterial and/or other manual input from the user, based on facility typeinformation derived from the ticket information.

In some embodiments, once the type of facility being marked has beendetermined, processor 118 may select a facilities map or facilities mapdata to render a display on display 146 by determining the currentgeo-location of the marking device and selecting a facilities map orfacilities map data corresponding to the facility type being markedbased on the current location of the marking device. Processor 118 maydetermine the current geo-location of the marking device from locationtracking system 130 and may select a facilities map or facilities mapdata for the type of facility being marked that includes the currentgeo-location. For example, if the current location of the marking deviceis 2650.9348,N,08003.5057,W, and the type of facility is electric powerlines, processor 118 may access facilities map data that covers an areaincluding 2650.9348,N,08003.5057,W and includes data indicating thelocation of electric power lines in this area, and may render a mapimage on display 146 showing the area and location of the electric powerlines in that area.

Other techniques for automatically selecting a facilities map orfacilities map data to render a displayed image may be used. Forexample, in some embodiments, processor 118 may select a facilities mapor facilities map data to be displayed using information from the ticketfor a particular locate operation. For example, an address from theticket may be used to select facilities map data that covers thegeographic area in which the address is located. In some embodiments,one or more member codes from the ticket may be used to determine afacility type that is to be marked and automatically select theappropriate facilities map data for that facility type. For example, ifa ticket includes a member code for the gas company, processor 118 mayautomatically select gas facilities map data. In some situations, aticket may include multiple member codes corresponding to differentutility types. In such situations, standard operating procedure may beused to determine which facilities map to automatically select first.For example, a ticket may include member codes for the gas company andthe electric company. Standard operating procedure may be specify thatgas is to be marked before electric and, as such, processor 118 mayautomatically select the gas facilities map data to be displayed firstand, once the gas locate and marking operation is complete, mayautomatically select the electric facilities map to be displayed next.

In some embodiments, information about the entity that requested thatthe locate operation be performed may be used in automatically selectingfacilities map data. For example, if the electric company requested thatthe locate operation be performed, processor 118 may automaticallyselect the electric facilities map data to be visually rendered anddisplayed.

In addition, in some embodiments, facilities map data may be selectedbased on a virtual white line (VWL) image that includes markings imposedon an image that delimit an area in which excavation is planned. Thus,for example, processor 118 may select facilities map data that includesthe area indicated by the markings.

In some embodiments, once facilities map data has been automaticallyselected, a portion of the facilities map or facilities map data torender an image on display 146 may be identified. That is, thefacilities map data that has been automatically selected may cover anarea significantly larger than the work site/dig area at which a locateand/or marking operation is being conducted, and thus only a portion ofthe selected map data needs to be displayed on display 146. Accordingly,in some embodiments, the map viewer application 113 executing onprocessor 118 may display only a portion of the facilities map data ondisplay 146. The portion of the facilities map to be displayed may beselected in a variety of ways. For example, in some embodiments, atechnician may have the ability to manually select the portion of afacilities map that is desired to be displayed on display 146. As anexample, once a particular facilities map has been automaticallyselected, the facilities map may be displayed on display 146 at adefault zoom level, centered at the current geo-location of the markingdevice. If the technician desires to a view a different portion of themap or adjust the zoom level, the technician may pan or scroll to adifferent part of the map and adjust the zoom level using the controlsof user interface 126.

In some embodiments, in addition to or instead of providing a technicianwith the capability to manually select a portion of a facilities mapdata to be displayed, processor 118 may automatically select a portionof the facilities map data to be displayed. For example, in someembodiments, processor 118 may select a portion of the selectedfacilities map data to be displayed based on one or more aspects of theticket information pursuant to which the locate and/or marking operationis being performed. In particular, as noted above, the ticketinformation generally includes some description of the work site/digarea (in which excavation, digging or otherwise disturbing the ground isanticipated). While conventionally such information about the worksite/dig area may be included as text comments in the ticketinformation, in some instances the ticket information may include adigital image (e.g., an aerial image) of a geographic areasurrounding/proximate to the work site, on which are placed (e.g., viaan electronic drawing tool) one or more dig area indicators to indicateor delimit a dig area. These marked-up digital images may be savedtogether with metadata pertaining to various information in the images.

An example of a drawing application that may be used to create suchmarked-up images including dig area indicators is described in U.S.patent application Ser. No. 12/366,853 filed Feb. 6, 2009, entitled“Virtual white lines for delimiting planned excavation sites;” U.S.patent application Ser. No. 12/475,905 filed Jun. 1, 2009, entitled“Virtual white lines for delimiting planned excavation sites of stagedexcavation projects;” U.S. patent application Ser. No. 12/422,364 filedApr. 13, 2009, entitled “Virtual white lines (VWL) application forindicating a planned excavation or locate path.” Each of these patentapplications is hereby incorporated by reference herein in its entirety.

In one example, the dig area indicators in a marked-up image may includetwo-dimensional (2D) drawing shapes, shades, points, symbols,coordinates, data sets, or other indicators to indicate on a digitalimage the dig area in which excavation is to occur. To generate theelectronic image having dig area indicators, an image (e.g., an aerialimage) of the work site may be sent to an excavator via a network, theexcavator may use a computing device executing the drawing applicationto create a marked-up image by marking up the image to include one ormore dig area indicators precisely delimiting one or more dig areaswithin the work site and, in response, the marked-up image may bereceived from the excavator via the network.

As noted above, a marked-up image may include metadata corresponding toany markings or content in the image; in particular, geographicinformation including geographic coordinates (e.g., latitude andlongitude values) for any dig area indicators on the marked-up image mayaccompany or be included in an image file as metadata, and thesegeographic coordinates may be employed in a variety of manners to selecta portion of the facilities map data to be displayed on display 146.

For example, in some embodiments, the portion of the facilities map datato be displayed may be selected to include all or a portion of the digarea as indicated on the marked-up image. In particular, in oneexemplary implementation, geographic coordinates associated with asingle dig area indicator may be used to select facilities map contentsthat relates only to a geographic area including the geographiccoordinates for the dig area indicator, or contents that falls within apredetermined radius of the geographic coordinates for the dig areaindicator or a polygon-shaped buffer zone around the geographiccoordinates for the dig area indicator. In yet another example,geographic coordinates associated with multiple dig area indicators thatdelimit a specific dig are may be used to select only contents of thefacilities map that corresponds to the delimited dig area. In yetanother embodiment, the contents of the facilities map that correspondsto the delimited dig area may be displayed with a “buffer frame” aroundthe delimited dig area (e.g., to provide some margins for the viewedsubject matter). Accordingly, it should be appreciated that in someembodiments, the dig area indicator coordinates may identify a pluralityof points along a perimeter of the delimited dig area, and thesecoordinates may be used to select specific geographic information fromthe facilities maps (e.g., filter out geographic information outside ofthe delimited dig area). In other embodiments, the dig area indicatorcoordinates may identify a single point, in which case the coordinatesmay be used to select particular information based at least in part onthe coordinates for the single point.

In some embodiments, the map viewer application 113 executing onprocessor 118 may automatically select an orientation of the map orportion of the map that is displayed on display 146 based on thedirection in which a technician of the marking device is moving. In someconventional techniques for displaying map information, a displayed mapgenerally is oriented so that north is at the top of the display andsouth is at the bottom of the display. However, the inventors haveappreciated that when displaying a facilities map or portion thereof ona marking device during a locate and/or marking operation, orienting themap such that the direction in which the technician is moving is at thetop of the map may aid the technician in identifying the location ofunderground facilities relative to his or her current position. Thus,for example, if the technician is walking north, then the map viewerapplication may display the selected portion of the map such that northis at the top of the screen. If the technician turns left and is walkingwest, then the map viewer application may re-orient the selected portionof the map such that west is at the top of the screen. In this manner,the map viewer application 113 executing on processor 118 may update theportion and/or the orientation of the facilities map that is beingdisplayed on display 146 in essentially real-time (e.g., update one ormore of pan, zoon, and orientation as the technician moves from oneplace to another during the operation).

The map viewer application 113 may determine the direction in which atechnician is walking using any of a variety of techniques. For example,in some embodiments, processor 118 may monitor the current geo-locationof the marking device as indicated by location tracking system 130,determine the direction in which the marking device is moving based onchanges in the geo-location, and provide this direction to the mapviewer application. For example, in some embodiments processor 118 maydetermine the direction in which the marking device is moving byobtaining the current heading from the electronic compass.

In some embodiments, marking device 110 may include other devices thatmay be used to determine the direction in which the marking device ismoving, such as a compass, an accelerometer, and/or an inclinometer.Thus, in some embodiments, processor 118 may use these devices insteadof or in addition to location tracking system 130 to determine thedirection in which the marking device is moving. For example, in someembodiments, the compass may be used to determine a heading in which themarking device is moving. In other embodiments, the accelerometer and/orinclinometer may be used to determine the direction in which the markingdevice is moving.

To demonstrate the concept of automatically orienting and positioning aportion of a facilities map based on technician/device movement andheading, FIG. 15 illustrates an example of a video frame sequence 400that may be displayed on display 146 of marking device 110 as atechnician moves the marking device to different geo-locations during alocate and/or marking operation. To illustrate video frame sequence 400,FIG. 15 shows an example facilities map 410, which is the facilities mapto be displayed on display 146. Facilities map 410 shows, for example,an intersection 412 of Roosevelt Avenue, which runs east and west, andWalnut Street, which runs north and south. Installed along RooseveltAvenue and/or Walnut Street is a first underground facility 414 and asecond underground facility 416. By way of example, video frame sequence400 shows a frame sequence that is presented on display 146 (e.g., bythe map viewer application 113) to the technician while in the processof locating and/or marking the first underground facility 414. Eachframe of video frame sequence 400 represents a segment of facilities map410 that is being displayed.

Referring to FIG. 15, as the locate technician moves in a northerlydirection along Walnut Street, frame 1 of video frame sequence 400 thatis displayed on display 146 shows underground facility 414 at the southend of Walnut Street with respect to facilities map 410. Additionally,frame 1 is oriented on display 146 with a north heading.

As the locate technician continues to move in a northerly directionalong Walnut Street, frame 2 of video frame sequence 400 that isdisplayed on display 146 shows underground facility 414 whileapproaching intersection 412 of facilities map 410. Additionally, frame2 is still oriented on display 146 with a north heading.

As the locate technician continues to move in a northerly directionthrough intersection 412, frame 3 of video frame sequence 400 that isdisplayed on display 146 shows underground facility 414 at intersection412. Additionally, frame 3 is still oriented on display 114 with a northheading.

As the locate technician changes direction and moves in a westerlydirection along Roosevelt Avenue, frame 4 of video frame sequence 400that is displayed on display 146 shows underground facility 414 whileexiting intersection 412 along Roosevelt Avenue. Additionally, frame 4the orientation of facilities map 410 on display 146 has been updatedfrom a north heading to a west heading.

As the locate technician continues to move in a westerly direction alongRoosevelt Avenue, frame 5 of video frame sequence 400 that is displayedon display 146 shows underground facility 414 at the west end ofRoosevelt Avenue with respect to facilities map 410. Additionally, frame5 is still oriented on display 146 with a west heading.

The inventors have appreciated that, in some situations where the locatetechnician is moving in a particular direction, the locate technicianmay reach a location that is at the end of a the portion of the map thatis currently being displayed, such that if the technician were tocontinue to move along a vector that includes a component in thatdirection, his or her location will no longer be a location on theportion of the map that is currently being displayed, but rather may bea location that is in a different map portion.

Thus, in some embodiments, when a location technician moves from alocation that is on the map portion currently being displayed to alocation that is not on the map portion that is currently beingdisplayed, processor 118 may determine that the technician has moved offthe map portion that is currently being displayed. Processor 118 maythen identify and select additional map data (e.g., stored in the localmemory 122 of the marking device, or retrieved from a library/archivestored on remote computer 150) that includes the location to which thetechnician has moved and cause the map viewer application 113 to displaythis other map, in a manner similar to that discussed above inconnection with appropriate selection of maps/images for display.

In addition, in some embodiments, it may be desired to display a mapsuch that the current location of the technician is roughly centered onthe display. In this way, as the technician moves, the portion of themap that is displayed is adjusted so that the geographic location oftechnician on the map is displayed roughly in the center of the display.In such embodiments, the technician may be at a geographic location thatis near or at the end of the currently displayed map portion. Thus, ifthe current location of the technician were to be displayed at roughlythe center of the display, then a portion of the display may be leftblank because the map data that belongs in that portion of the displayis not in the map currently being displayed. Thus, in some embodiments,to address this issue, processor 118 may determine when the technicianis at a location that warrants additional map data to be displayed onthe display at the same time, determine which additional map dataincludes the desired data, stitch together a map image using theadditional map data, and cause this “stitched together” image to bedisplayed on the display.

While the concepts described immediately above (e.g., updating pan, zoomand or orientation of displayed content based on technician/devicemovement and heading) were discussed for purposes of illustration usingfacilities map information, it should be appreciated that the foregoingdiscussion applies similarly to other types of image information (e.g.,from one or more of the input images discussed above in Section III).

FIG. 16 illustrates a flow diagram of a process 500 for selecting andviewing facilities map information or other image information on amarking device, according to one embodiment of the present invention.Process 500 begins at act 512 where the type of facility to be marked isestablished manually or automatically using, for example, any of thetechniques discussed above. The process then continues to act 514, wherethe location tracking system of the marking device is queried for thecurrent geo-location information. The geo-location data from locationtracking system 158 may be provided, in a variety of different formats,including for example, in degrees, minutes, and seconds (i.e., DDD° MM′SS.S″), degrees and decimal minutes (DDD° MM.MMM′), decimal degrees(DDD.DDDDD°), and/or any combination thereof.

The process next continue to act 516, where facilities map data thatmatches the determined facility type determined in act 512 and thegeo-location determined in act 514 is identified. The process thencontinues to act 518, where the map viewer application reads in theidentified facilities map data, preparing to present an image of thisfacilities map on the display of the marking device. The processor thencontinues to act 520, where the current heading (i.e., the direction inwhich the marking device is moving) is determined from, for example, thelocation tracking system, compass, inclinometer, and/or accelerometer.Once the current heading is determined, the process continues to act522, where a map or map image segment is oriented according to thedetermined heading and centered according to the current geo-location ofthe marking device, and the facilities map image is presented on thedisplay of the marking device.

In some embodiments, the marking device may alert the technician when heor she is at a location of a facility line, as indicated by thefacilities map data. Thus, in some embodiments, the process may continueto act 524, where an alert to the locate technician may be generatedbased on comparing current geo-location of the marking device to thegeo-location of the facilities of the displayed facilities map. Inparticular, in one exemplary implementation, the geo-location of thefacilities of the displayed facilities map constitutes “referenceinformation,” to which “field information” in the form of thegeo-location of the marking device (e.g., respective geo-locations ofdispensed marking material) may be compared. Various methods andapparatus for comparing field information in the context of locate andmarking operations to reference information derived from facilities mapsis discussed in U.S. application Ser. No. 12/571,356, filed Sep. 30,2009, and entitled, “Method And Apparatus For Analyzing Locate AndMarking Operations With Respect To Facilities Maps,” which isincorporated herein by reference in its entirety.

In one example, processor 118 may compare the geo-location data oflocation tracking system 130 to the geo-location information in thedisplayed facilities map. When the two geo-locations substantially match(within a certain acceptable tolerance), an audible indicator, such as abuzzer or alarm may be activated, a tactile indicator such as a devicethat vibrates the handle of the marking device, and/or a visualindicator, such as an LED of user interface 126, may be activated inorder to alert the locate technician that he or she is at or near thelocation of the target facility to be marked.

In other embodiments, if the location of the marking device differs fromthe location at which the facilities map(s) indicate the facility lineto be marked is located by at least a threshold distance (e.g. six feetor any other suitable threshold distance), processor 118 may cause analert (e.g., an audible indicator, a tactile indicator, and/or a visualindicator) to the technician to be activated. In addition, anydiscrepancies between the locations at which marking material wasdispensed and the locations of the facility lines to be marked asindicated on the facilities map may be logged and later evaluated todetermine whether the discrepancy is a result of facilities mapinaccuracy or locate technician error.

As shown in FIG. 16, the acts of process 500 may repeat any number oftimes and at any programmed frequency (e.g., every 100 milliseconds)until the locate operation is complete. With each iteration of the actsof process 500, the map viewer application updates (or refreshes) thedisplay with the current facilities map information in order to reflectany changing geo-location and/or heading of the marking device as thetechnician performs the locate operation.

IV. OVERLAY OF MARKING INFORMATION ON DISPLAYED FACILITIES MAPINFORMATION OR OTHER IMAGE INFORMATION

The inventors have appreciated that, as a technician using a markingdevice dispenses marking material during a locate and marking operation,it may be useful to overlay, on displayed facilities map information orother displayed image information, electronic marks that indicate wherethe marking material was dispensed. This provides the locate technicianwith a visual representation of where marking material was dispensedrelative to the location of facility lines shown on the facilities map,and may accordingly provide a sense of how close the marking materialthat he or she dispensed is to the location of the facility lines, asindicated on the map. In addition, in some situations, it may bedesirable to overlay one or more indicators, such as a “you are here”icon or a pointer icon on the displayed facilities map or other imageinformation to provide the technician with a visual representation ofhis or her current location on the displayed portion of the map.

FIG. 17 is an example of a process that may be used to overlay data,such as electronic markings indicative of geo-locations at which markingmaterial was dispensed, a present location indicator or a “you are here”icon indicative of the current location of the marking device, or anyother type of data, on displayed facilities map information or otherimage information, according to one embodiment of the present invention.

The process of FIG. 17 begins at act 901, where the geo-location data ofthe marking information to be overlaid (e.g., geo-location datacorresponding to physical locate marks, or a current location mark) isdetermined/collected. For example, if the information to be overlaid isa current location mark or “you are here” icon indicative of the currentlocation of the marking device, the current location of the markingdevice may be determined from location tracking system 130. If theinformation to be overlaid is an electronic mark indicative of ageo-location at which marking material was dispensed (e.g., to create aphysical locate mark on ground, pavement or other surface), thegeo-location data at which marking material was dispensed may becollected from the location tracking system 130 in response to actuationof the marking device and/or determined, for example, from theelectronic record 135 generated and stored by the marking device. Thatis, as discussed above, in some embodiments, each time the markingdevice 110 is actuated, the location tracking system may be polled toprovide one or more geo-location data points that may be overlaid ondisplayed facilities map information or other image informationessentially in real-time as the data is collected, and/or thegeo-location data may be logged as data event entries in the electronicrecord 135 and the electronic record 135 may be accessed thereafter toobtain geo-location data for overlaying on displayed facilities map orother image information.

Table 2 below shows another example of marking device data that may becaptured as the result of, for example, one or more actuations of amarking device. Specifically, Table 2 illustrates multiple “actuationdata sets” of an electronic record of a marking operation as generatedby a marking device, in which each actuation data set includesinformation associated with multiple actuation event entries loggedduring a corresponding actuation of the marking device and dispensing ofmarking material. Table 2 shows three actuation data sets of anelectronic record, corresponding to three actuations of the markingdevice (e.g., act-1, act-2, and act-3). As may be appreciated from theinformation shown in Table 2, in some embodiments multiple pieces ofgeo-location data may be logged for each actuation of a marking device(in addition to various other information). However, it should beappreciated that the present invention is not limited in this respect,and that multiple pieces of geo-location data per actuation are notnecessarily required for overlay on displayed facilities map or otherimage information.

TABLE 2 Example actuation data set for act-1 act-1 Service provider ID0482 User ID 4815 Device ID 7362 T1 timestamp data Jul. 12, 2008;09:35:15.2 T2 timestamp data Jul. 12, 2008; 09:35:16.1 Duration (Δt)00:00:00.9 T1 geo-location data 2650.9348, N, 08003.5057, W 1^(st)interval location data 2650.9353, N, 08003.5055, W 2^(nd) intervallocation data 2650.9356, N, 08003.5055, W — — — — — — Nth intervallocation data 2650.9246, N, 08003.5240, W T2 geo-location data2650.9255, N, 08003.5236, W Product data Color = Red, Brand = ABC,Type/Batch = 224B-1 Locate request data Requestor: XYZ ConstructionCompany, Requested service address: 222 Main St, Orlando, FL Exampleactuation data set for act-2 act-2 Service provider ID 0482 User ID 4815Device ID 7362 T1 timestamp data Jul. 12, 2008; 09:35:17.5 T2 timestampdata Jul. 12, 2008; 09:35:18.7 Duration (Δt) 00:00:01.2 T1 geo-locationdata 2650.9256, N, 08003.5234, W 1^(st) interval location data2650.9256, N, 08003.5226, W 2^(nd) interval location data 2650.9256, N,08003.5217, W — — — — — — Nth interval location data 2650.9260, N,08003.5199, W T2 geo-location data 2650.9266, N, 08003.5196, W Productdata Color = Red, Brand = ABC, Type/Batch = 224B-1 Locate request dataRequestor: XYZ Construction Company, Requested service address: 222 MainSt, Orlando, FL Example actuation data set for act-3 act-3 Serviceprovider ID 0482 User ID 4815 Device ID 7362 T1 timestamp data Jul. 12,2008; 09:35:18.7 T2 timestamp data Jul. 12, 2008; 09:35:19.8 duration(Δt) 00:00:01.1 T1 geo-location data 2650.9273, N, 08003.5193, W 1^(st)interval location data 2650.9281, N, 08003.5190, W 2^(nd) intervallocation data 2650.9288, N, 08003.5188, W — — — — — — Nth intervallocation data 2650.9321, N, 08003.5177, W T2 geo-location data2650.9325, N, 08003.5176, W Product data Color = Red, Brand = ABC,Type/Batch = 224B-1 Locate request data Requestor: XYZ ConstructionCompany, Requested service address: 222 Main St, Orlando, FL

Thus, the geo-location(s) at which marking material was dispensed may beobtained from these electronic records, and/or may be collectedessentially in real-time as the marking operation is being performed.Once the geo-location data to be overlaid on the displayed informationis determined, the process continues to optional act 903, where thisgeo-location data may be converted, if necessary, to the spatialreference frame used by the facilities map (or other image) from whichthe information displayed on the display 146 is derived.

As known in the relevant art, a geographic or “global” coordinate system(i.e., a coordinate system in which geographic locations on Earth areidentified by a latitude and a longitude value, e.g., (LAT,LON)) may beused to identify geographic locations of locate marks and a facilityline. In a “geocentric” global coordinate system (i.e., a coordinatesystem in which the Earth is modeled as a sphere), latitude is definedas the angle from a point on the surface of a sphere to the equatorialplane of the sphere, whereas longitude is defined as the angle east orwest of a reference meridian between two geographical poles of thesphere to another meridian that passes through an arbitrary point on thesurface of the sphere. Thus, in a geocentric coordinate system, thecenter of the Earth serves as a reference point that is the origin ofthe coordinate system. However, in actuality the Earth is not perfectlyspherical, as it is compressed towards the center at the poles.Consequently, using a geocentric coordinate system can result ininaccuracies.

In view of the foregoing, the Earth is typically modeled as an ellipsoidfor purposes of establishing a global coordinate system. The shape ofthe ellipsoid that is used to model the Earth and the way that theellipsoid is fitted to the geoid of the Earth is called a “geodeticdatum.” In a “geodetic” global coordinate system, the latitude of apoint on the surface of the ellipsoid is defined as the angle from theequatorial plane to a line normal to the reference ellipsoid passingthrough the point, whereas the longitude of a point is defined as theangle between a reference plane perpendicular to the equatorial planeand a plane perpendicular to the equatorial plane that passes throughthe point. Thus, geodetic latitude and longitude of a particular pointdepends on the geodetic datum used.

A number of different geodetic global coordinate systems exist that usedifferent geodetic datums, examples of which include WGS84, NAD83,NAD27, OSGB36, and ED50. As such, a geographic point on the surface ofEarth may have a different latitude and longitude values in differentcoordinate systems. For example, a stop sign at the corner Maple St. andMain St. may have a latitude and longitude of (LAT₁, LON₁) in the WGS84coordinate system, but may have a latitude and longitude of (LAT₂, LON₂)in the NAD83 coordinate system (where LAT₁≠LAT₂ and/or LON₁≠LON₂). Thus,when comparing one geographic point to another geographic point todetermine the distance between them, it is desirable to have bothgeographic points in the same global coordinate system.

Additionally, when determining a geographic location based oninformation derived from a map (e.g., a facilities map), the coordinatesystem provided by the map may not be a global coordinate system, butrather may be a “projected” coordinate system. As appreciated in therelevant art, representing the curved surface of the Earth on a flatsurface or plane is known as a “map projection.” Representing a curvedsurface in two dimensions causes distortion in shape, area, distance,and/or direction. Different map projections cause different types ofdistortions. For example, a projection could maintain the area of afeature but alter its shape. A map projection defines a relation betweenspherical coordinates on the globe (i.e., longitude and latitude in aglobal coordinate system) and flat planar x,y coordinates (i.e., ahorizontal and vertical distance from a point of origin) in a projectedcoordinate system. A facilities map may provide geographic locationinformation in one of several possible projected coordinate systems.

Thus, to overlay geo-location data (e.g., obtained from the locationtracking system 130 of the marking device) on displayed facilities mapinformation (or other image information), it is desirable to have thegeo-location data and the facilities map information represented in thesame geodetic global coordinate system or projected coordinate system(projected from the same geodetic geographical coordinate system). Forexample, in some embodiments, the geo-location data points obtained bythe location tracking system of the marking device may be provided asgeo-location data in the WGS84 coordinate system (i.e., the coordinatesystem typically used by GPS equipment), whereas the facilities mapinformation may be expressed in the NAD83 coordinate system. Thus, atact 903, the geo-location data coordinates provided by the locationtracking system of the marking device may be converted to the NAD83coordinate system so that they may be appropriately overlaid on thedisplayed facilities map information.

The process next continues to act 905, where the data, converted if/asappropriate, may be overlaid on the information displayed on display146, such that display 146 displays both the facilities map/imageinformation and the overlaid data. For example, if the techniciandispensed marking material at 2650.9273,N,08003.5193,W (decimal degrees)in the coordinate system used by the facilities map, an electronic markmay be overlaid on the displayed facilities map at the portion of thefacilities map that corresponds to 2650.9273,N,08003.5193,W. Similarly,if the current location of the marking device is2680.5243,N,08043.4193,W in the coordinate system used by the facilitiesmap, then a “you are here” icon may be overlaid on the displayedfacilities map at the portion of the facilities map that corresponds to2680.5243,N,08043.4193,W.

Any one of a number of different techniques may be used to overlay dataon the displayed facilities map or image. In some embodiments, the datato be visually rendered on the facilities map or image is mapped to adisplay field of the display device to ensure that the geo-location datafor the data to be overlaid is displayed over the proper place on thedisplayed facilities map or image. For example, in one exemplaryimplementation, a transformation may be derived using informationrelating to the available display field (e.g., a reference coordinatesystem using an appropriate scale for a given display field of a displaydevice) to map data points in the geo-location data for the data to beoverlaid to the available display field. Once such a transformation isderived, the data to be overlaid may be rendered in the display field byapplying the transformation to the geo-location data for the data to beoverlaid.

In the illustrative processes of FIGS. 16 and 17, a separate facilitiesmap may be selected for each facility type (or facility company).However, in some embodiments, rather than using a separate facilitiesmap for each facility type or facility company, an aggregated facilitiesmap or facilities map database may be generated by combining data frommultiple facilities maps, and data from the aggregated facilities mapdatabase may be selected and displayed on the display of the markingdevice. For example, if gas lines, water lines, and power lines are tobe marked during a locate and/or marking operation in a particularlocation, an aggregated facilities map database may be generated byaccessing the facilities map from the gas company for the location, thefacilities map from the water company for the location, and thefacilities map from the electric company from the location, extractinginformation about the location of map features (e.g., facility lines,streets, and/or other map features) from each of these facilities maps,converting the locations to a common frame of reference (e.g., using thetechniques discussed above), and combining the extracted features into adatabase (e.g., from which a single aggregated map may be derived).Thus, rather than performing the process of FIG. 16 or 17 three timeswith three separate facilities maps (i.e., once using the gas facilitiesmap, once using the water facilities map, and once using the electricfacilities map), the aggregated facilities map may be used each time.

As with a facilities map for a single type of facility, in someembodiments, an electronic representation of the physical locate marksdispensed on the ground, an electronic representation of the currentlocation of the technician (e.g., a you are here icon), or otherinformation may be generated and rendered visually (i.e., overlaid) onthe aggregated facilities map.

In some embodiments, the map or image data and the data to be overlaid(e.g., the electronic representation of the physical locate marksdispensed on the ground or the electronic representation of the currentlocation of the technician), may be displayed as separate “layers” ofthe visual rendering, such that a viewer of the visual rendering mayturn on and turn off displayed data based on a categorization of thedisplayed data. For example, all facilities map or image data may becategorized generally under one layer designation (e.g., “Reference”),and independently enabled or disabled for display (e.g., hidden)accordingly. Similarly, all overlaid data may be categorized generallyunder another layer designation (e.g., “Field”) and independentlyenabled or disabled for display accordingly. Respective layers may beenabled or disabled for display in any of a variety of manners; forexample, in one implementation, a “layer directory” or “layer legend”pane may be included in the display field (or as a separate windowselectable from the display field of the visual rendering), showing allavailable layers, and allowing a viewer to select each available layerto be either displayed or hidden, thus facilitating comparative viewingof layers.

Furthermore, any of the above-mentioned general categories for layersmay have sub-categories for sub-layers, such that each sub-layer mayalso be selectively enabled or disabled for viewing by a viewer. Forexample, under the general layer designation of “Field,” differentfacility types that may have been marked (and indicated in the fielddata by color, for example) may be categorized under different sub-layerdesignations (e.g., “Field—Electric;” “Field—Gas;” etc.); in thismanner, a viewer may be able to hide the electric field data whileviewing the gas field data, or vice versa, in addition to having theoption to view or hide all field data.

In some embodiments, a variety of other sub-layers may be used. Forexample, sub-layers may be provided for certain types of map metadata.In one example, landmarks (e.g., poles, pedestals, curbs, hydrants,street lights, and/or other types of landmarks) may be a separatesub-layer that can be toggled on and off from the display. In anotherexample, sub-layers for a particular facility type may be provided. Asone example, within the sub-layer “Field—Electric,” a sub-layer may beprovided for aerial electric lines, and another sub-layer may beprovided for underground electric lines. As another example, for asub-layer for telephone lines (e.g., “Field—Telephone”), sub-layers maybe provided for the type of material used. For example, one sub-layermay be provided for copper telephone lines, while another sub-layer maybe provided for fiber lines.

Similarly, in embodiments in which an aggregated facilities map isdisplayed on the display device, the “Reference” layer may havesub-layers for each facility type in the aggregated facilities map. Thatis, each facility type in the aggregated facilities map may have adifferent sub-layer designation, such that a viewer may be able toindividually select which sub-layers are displayed on the displaydevice. For example, if an aggregated facilities map includesinformation from a gas facilities map, an electric facilities map, and acable TV (CATV) facilities map, the data from the gas facilities map,the data from the electric facilities map, and the data from the CATVfacilities may each be a separate sub-layer. As such, the viewer may beable to select which of these layers he or she wishes to be displayed onthe display, and which he or she wishes to be hidden.

FIG. 18 shows a generic display device 3000 having a display field 3005with exemplary content for purposes of explaining some concepts germaneto display layers, according to one embodiment. For example, all markinginformation may be categorized generally under one layer designation3030 (“marking layer”) and independently enabled or disabled for displayaccordingly, all landmark information may be categorized generally underyet another layer designation 3040 (“landmark layer”) and independentlyenabled or disabled for display accordingly, and all referenceinformation may be categorized generally under yet another layerdesignation 3050 (“reference layer”) and independent enabled or disabledfor display. Respective layers may be enabled or disabled for display inany of a variety of manners; for example, in one implementation, a“layer directory” or “layer legend” pane 3010 may be included in thedisplay field 3005 (or as a separate window selectable from the displayfield of the visual rendering), showing all available layers, andallowing a viewer to select each available layer to be either displayedor hidden, thus facilitating comparative viewing of layers.

Furthermore, any of the above-mentioned general categories for layersmay have sub-categories for sub-layers, such that each sub-layer mayalso be selectively enabled or disabled for viewing by a viewer. Forexample, under the general layer designation of “marking layer,”different facility types that may have been marked during a locateand/or marking operation (and indicated in the locate information bycolor, for example) may be categorized under different sub-layerdesignations (e.g., designation 3032 for “marking layer—electric;”designation 3034 for “marking layer—gas;” etc.); in this manner, aviewer may be able to hide only the electric marking information whileviewing the gas marking information, or vice versa, in addition tohaving the option to view or hide all marking information. Under thelayer designation of “landmark layer” different types of landmarks maybe categorized under different sub-layer designations (e.g., designation3042 for water/sewer landmarks, designation 3044 for cable TV landmarks,and designation 3045 for buildings). Under the layer designation of“reference layer” different types of reference information may becategorized under different sub-layer designations (e.g., designation3052 for base map information, designation 3054 for dig area indicators,designation 3056 for facility lines).

As shown in the example of FIG. 18, of the marking, landmark, andreference layers, only the electric sub-layer of the marking layer andthe buildings sub-layer of the landmark layer are enabled for display.Accordingly, in FIG. 18, only the electronic markings 1010 indicatingwhere marking material for a power line was dispensed and building 950appear in the electronic rendering 1000A shown in FIG. 18.

Virtually any characteristic of the information available for displaymay serve to categorize the information for purposes of displayinglayers or sub-layers. In particular, with respect to informationobtained during performance of a locate and/or marking operation, any ofa variety of exemplary constituent elements of such information (e.g.,timing information, geographic information, service-related information,ticket information, facility type information) may be categorized as asub-layer, and one or more sub-layers may further be categorized intoconstituent elements for selective display (e.g., as sub-sub-layers).For example, timing information may be used to categorize the markinginformation based on a time at which marking material was dispensed,such that one sub-layer may include an electronic representation of thelocations at which marking material was dispensed during a particulartime window. Geographic information may be used to categorize themarking information based on a location at which marking material wasdispensed, so that one sub-layer may include electronic representationsof the locations at which marking material was dispensed for aparticular geographic area.

Service-related information may include, for example, a service-provideridentifier indicative of a service-provider overseeing the locate and/ormarking operation, a technician identifier representing a technicianthat performs the locate operation and/or the marking operation, adevice identifier representing a device used by the technician duringthe locate operation and/or the marking operation, and a statusidentifier representing an operating status of the at least one device.Any such service-related information may be used to categorize themarking information into one or more sub-layers.

Ticket information may include a ticket number identifying the ticket, aparty identifier representing a party requesting the locate and/or themarking operation, a facility identifier representing a type and/ornumber of one or more facilities to be detected and/or marked in thelocate and/or the marking operation, and/or a ground type identifierrepresenting a ground type for a work site and/or dig area at which thelocate and/or the marking operation is performed. Any such ticketinformation may be used to categorize the marking information into oneor more sub-layers.

Similarly, with respect to the “Reference” layer, virtually anycharacteristic of the information available for display in this layermay serve to categorize the information for purposes of displayingsub-layers. For example, landmarks, particular types of landmarks,particular types of facility lines, dig area indicators (e.g., virtualwhite lines), facility lines owned by a particular entity, and/orfacility lines in a particular geographic area may each be a separatesub-layer.

In some embodiments, processor 118 may automatically select whichsub-layers in the “Reference” layer and/or the “Field” layer aredisplayed. For example, in some embodiments, processor 118 mayautomatically select particular sub-layers to be displayed based on thetype of facility being marked. As discussed above, processor 118 maydetermine the type of facility being marked in a variety of ways,including for example, based on the color of the marking material in themarking material dispenser of the marking device. Based on the color ofthe marking material, processor 118 may automatically select certainsub-layers to be displayed and may select certain other sub-layers tonot be displayed. For example, processor 118 may automatically selectsub-layers related to facility type corresponding to the color of themarking material to be displayed, and may select sub-layers not relatedto that facility type to not be displayed. As one example, if themarking material in the marking material dispenser of the marking deviceis red, then processor 118 may automatically select for display one ormore sub-layers for the “Field” layer that pertain to electric lines andmay not display sub-layers related to other utility types. Processor 118may also select sub-layers for the “Reference” layer that pertain toelectric lines and may not display sub-layers related to other utilitytypes.

In general, it should be appreciated that any constituent element ofinformation from the field (e.g., marking information and/or landmarkinformation) may be used as a basis for automatically selecting/enablingfor display one or more sub-layers of reference/image information. Forexample, if landmark information indicates that acquired landmarkgeo-location data is associated with a hydrant, a “water facilities”sub-layer and/or a “water landmarks” sub-layer may be automaticallyselected from the “Reference” layer for display in the display field.Similarly, if marking information indicates that a gas main is beingmarked, a “gas facilities” sub-layer and/or a “gas landmarks” sub-layermay be automatically selected from the “Reference” layer for display inthe display field. The foregoing are merely illustrative examples ofautomatic selection/enabling of Reference sub-layers, and the inventiveconcepts discussed herein are not limited in these respects.

V. CONCLUSION

While various inventive embodiments have been described and illustratedherein, those of ordinary skill in the art will readily envision avariety of other means and/or structures for performing the functionand/or obtaining the results and/or one or more of the advantagesdescribed herein, and each of such variations and/or modifications isdeemed to be within the scope of the inventive embodiments describedherein. More generally, those skilled in the art will readily appreciatethat all parameters, dimensions, materials, and configurations describedherein are meant to be exemplary and that the actual parameters,dimensions, materials, and/or configurations will depend upon thespecific application or applications for which the inventive teachingsis/are used. Those skilled in the art will recognize, or be able toascertain using no more than routine experimentation, many equivalentsto the specific inventive embodiments described herein. It is,therefore, to be understood that the foregoing embodiments are presentedby way of example only and that, within the scope of the appended claimsand equivalents thereto, inventive embodiments may be practicedotherwise than as specifically described and claimed. Inventiveembodiments of the present disclosure are directed to each individualfeature, system, article, material, kit, and/or method described herein.In addition, any combination of two or more such features, systems,articles, materials, kits, and/or methods, if such features, systems,articles, materials, kits, and/or methods are not mutually inconsistent,is included within the inventive scope of the present disclosure.

The above-described embodiments can be implemented in any of numerousways. For example, the embodiments may be implemented using hardware,software or a combination thereof. When implemented in software, thesoftware code can be executed on any suitable processor or collection ofprocessors, whether provided in a single computer or distributed amongmultiple computers.

Further, it should be appreciated that a computer may be embodied in anyof a number of forms, such as a rack-mounted computer, a desktopcomputer, a laptop computer, or a tablet computer. Additionally, acomputer may be embedded in a device not generally regarded as acomputer but with suitable processing capabilities, including a PersonalDigital Assistant (PDA), a smart phone or any other suitable portable orfixed electronic device.

Also, a computer may have one or more input and output devices. Thesedevices can be used, among other things, to present a user interface.Examples of output devices that can be used to provide a user interfaceinclude printers or display screens for visual presentation of outputand speakers or other sound generating devices for audible presentationof output. Examples of input devices that can be used for a userinterface include keyboards, and pointing devices, such as mice, touchpads, and digitizing tablets. As another example, a computer may receiveinput information through speech recognition or in other audible format.

Such computers may be interconnected by one or more networks in anysuitable form, including a local area network or a wide area network,such as an enterprise network, and intelligent network (IN) or theInternet. Such networks may be based on any suitable technology and mayoperate according to any suitable protocol and may include wirelessnetworks, wired networks or fiber optic networks.

The various methods or processes outlined herein may be coded assoftware that is executable on one or more processors that employ anyone of a variety of operating systems or platforms. Additionally, suchsoftware may be written using any of a number of suitable programminglanguages and/or programming or scripting tools, and also may becompiled as executable machine language code or intermediate code thatis executed on a framework or virtual machine.

In this respect, various inventive concepts may be embodied as acomputer readable storage medium (or multiple computer readable storagemedia) (e.g., a computer memory, one or more floppy discs, compactdiscs, optical discs, magnetic tapes, flash memories, circuitconfigurations in Field Programmable Gate Arrays or other semiconductordevices, or other non-transitory medium or tangible computer storagemedium) encoded with one or more programs that, when executed on one ormore computers or other processors, perform methods that implement thevarious embodiments of the invention discussed above. The computerreadable medium or media can be transportable, such that the program orprograms stored thereon can be loaded onto one or more differentcomputers or other processors to implement various aspects of thepresent invention as discussed above.

The terms “program” or “software” are used herein in a generic sense torefer to any type of computer code or set of computer-executableinstructions that can be employed to program a computer or otherprocessor to implement various aspects of embodiments as discussedabove. Additionally, it should be appreciated that according to oneaspect, one or more computer programs that when executed perform methodsof the present invention need not reside on a single computer orprocessor, but may be distributed in a modular fashion amongst a numberof different computers or processors to implement various aspects of thepresent invention.

Computer-executable instructions may be in many forms, such as programmodules, executed by one or more computers or other devices. Generally,program modules include routines, programs, objects, components, datastructures, etc. that perform particular tasks or implement particularabstract data types. Typically the functionality of the program modulesmay be combined or distributed as desired in various embodiments.

Also, data structures may be stored in computer-readable media in anysuitable form. For simplicity of illustration, data structures may beshown to have fields that are related through location in the datastructure. Such relationships may likewise be achieved by assigningstorage for the fields with locations in a computer-readable medium thatconvey relationship between the fields. However, any suitable mechanismmay be used to establish a relationship between information in fields ofa data structure, including through the use of pointers, tags or othermechanisms that establish relationship between data elements.

Also, various inventive concepts may be embodied as one or more methods,of which an example has been provided. The acts performed as part of themethod may be ordered in any suitable way. Accordingly, embodiments maybe constructed in which acts are performed in an order different thanillustrated, which may include performing some acts simultaneously, eventhough shown as sequential acts in illustrative embodiments.

All definitions, as defined and used herein, should be understood tocontrol over dictionary definitions, definitions in documentsincorporated by reference, and/or ordinary meanings of the definedterms.

The indefinite articles “a” and “an,” as used herein in thespecification and in the claims, unless clearly indicated to thecontrary, should be understood to mean “at least one.”

The phrase “and/or,” as used herein in the specification and in theclaims, should be understood to mean “either or both” of the elements soconjoined, i.e., elements that are conjunctively present in some casesand disjunctively present in other cases. Multiple elements listed with“and/or” should be construed in the same fashion, i.e., “one or more” ofthe elements so conjoined. Other elements may optionally be presentother than the elements specifically identified by the “and/or” clause,whether related or unrelated to those elements specifically identified.Thus, as a non-limiting example, a reference to “A and/or B”, when usedin conjunction with open-ended language such as “comprising” can refer,in one embodiment, to A only (optionally including elements other thanB); in another embodiment, to B only (optionally including elementsother than A); in yet another embodiment, to both A and B (optionallyincluding other elements); etc.

As used herein in the specification and in the claims, “or” should beunderstood to have the same meaning as “and/or” as defined above. Forexample, when separating items in a list, “or” or “and/or” shall beinterpreted as being inclusive, i.e., the inclusion of at least one, butalso including more than one, of a number or list of elements, and,optionally, additional unlisted items. Only terms clearly indicated tothe contrary, such as “only one of” or “exactly one of,” or, when usedin the claims, “consisting of,” will refer to the inclusion of exactlyone element of a number or list of elements. In general, the term “or”as used herein shall only be interpreted as indicating exclusivealternatives (i.e. “one or the other but not both”) when preceded byterms of exclusivity, such as “either,” “one of,” “only one of,” or“exactly one of” “Consisting essentially of,” when used in the claims,shall have its ordinary meaning as used in the field of patent law.

As used herein in the specification and in the claims, the phrase “atleast one,” in reference to a list of one or more elements, should beunderstood to mean at least one element selected from any one or more ofthe elements in the list of elements, but not necessarily including atleast one of each and every element specifically listed within the listof elements and not excluding any combinations of elements in the listof elements. This definition also allows that elements may optionally bepresent other than the elements specifically identified within the listof elements to which the phrase “at least one” refers, whether relatedor unrelated to those elements specifically identified. Thus, as anon-limiting example, “at least one of A and B” (or, equivalently, “atleast one of A or B,” or, equivalently “at least one of A and/or B”) canrefer, in one embodiment, to at least one, optionally including morethan one, A, with no B present (and optionally including elements otherthan B); in another embodiment, to at least one, optionally includingmore than one, B, with no A present (and optionally including elementsother than A); in yet another embodiment, to at least one, optionallyincluding more than one, A, and at least one, optionally including morethan one, B (and optionally including other elements); etc.

In the claims, as well as in the specification above, all transitionalphrases such as “comprising,” “including,” “carrying,” “having,”“containing,” “involving,” “holding,” “composed of,” and the like are tobe understood to be open-ended, i.e., to mean including but not limitedto. Only the transitional phrases “consisting of” and “consistingessentially of” shall be closed or semi-closed transitional phrases,respectively, as set forth in the United States Patent Office Manual ofPatent Examining Procedures, Section 2111.03.

What is claimed is:
 1. A marking apparatus to mark a presence or anabsence of an underground facility, the marking apparatus comprising: ahousing; a marking dispenser holder coupled to the housing to hold areplaceable marking material; an actuator that, when actuated, causesdispensing of the marking material; a display device coupled to thehousing; at least one sensor, coupled to the housing, to outputgeographic information indicative of a geographic location of themarking apparatus; at least one memory; and at least one processor,communicatively coupled to the display device and the at least onememory, the at least one processor configured to cause a display of adigital image on the display device, the at least one processor furtherconfigured to generate the digital image based at least in part on firstdigital image data selected by the at least one processor, wherein: theat least one processor is configured to select the first digital imagedata based, at least in part, on: at least one of facilities map data,survey map data, land survey data, photographic image data, constructiondrawings, and engineering drawings; and the geographic informationoutput by the at least one sensor and indicative of the geographiclocation of the marking apparatus; and the at least one processorconfigured to overlay, on the displayed digital image, based at least inpart on the geographic location of the marking apparatus, at least oneelectronic marking representing a detected absence of the undergroundfacility.
 2. The marking apparatus of claim 1, wherein the at least oneprocessor is further configured to generate the digital image based atleast in part on first digital image data from a remote device.
 3. Themarking apparatus of claim 2, wherein the at least one processor isconfigured to store the first digital image data in the at least onememory.
 4. The marking apparatus of claim 2, wherein the first digitalimage data comprises at least one map image.
 5. The marking apparatus ofclaim 1, wherein the at least one processor is configured to store dataindicating a type of facility and the geographic location of the markingapparatus.
 6. The marking apparatus of claim 1, wherein the at least oneprocessor is configured to select a type of facility in response to auser input
 7. The marking apparatus of claim 1, wherein the at least oneprocessor is configured to determine a type of facility to be marked inresponse to information provided by the at least one sensor.
 8. Themarking apparatus of claim 7, wherein the at least on sensor comprisesat least one global position system (GPS) receiver that is coupled tothe housing.
 9. The marking apparatus of claim 8, wherein the markingapparatus further comprises an electronic compass, and wherein theinformation provided by the at least one sensor comprises informationindicative of a heading of the marking apparatus, and wherein the atleast one processor is configured to generate the digital image based atleast in part on the heading of the marking apparatus.
 10. The markingapparatus of claim 7, wherein the at least one sensor comprises amarking material sensing device configured to detect a color of themarking material in the marking dispenser holder, and wherein theinformation provided by the sensor comprises information indicative ofthe color of the marking material in the marking dispenser holder. 11.The marking apparatus of claim 1, wherein the at least one processor isconfigured to determine a type of facility to be marked based at leastin part on information obtained from a ticket associated with a locateoperation.
 12. The marking apparatus of claim 11, wherein theinformation obtained from the ticket comprises an address at which thelocate operation is requested to be performed.
 13. The marking apparatusof claim 12, wherein the information obtained from the ticket comprisesat least one member code indicative of the type of facility to be markedduring performance of the locate operation.
 14. The marking apparatus ofclaim 12, wherein the information obtained from the ticket comprisesinformation identifying an entity that requested performance of thelocate operation.
 15. The marking apparatus of claim 2, wherein the atleast one processor is configured to select the first digital image databased, at least in part, on a virtual white line image that indicates alocation at which excavation is planned.
 16. The marking apparatus ofclaim 2, wherein the first digital image data comprises first facilitiesmap data, wherein the at least one memory stores the facilities map dataincluding the first facilities map data, and wherein the at least oneprocessor is configured to select the first facilities map data from thefacilities map data stored in the at least one memory.
 17. The markingapparatus of claim 1, wherein the at least one processor is configuredto select an orientation at which to display, on the display device, thedigital image, based at least in part on heading information indicativeof a direction in which the marking apparatus is moving.
 18. The markingapparatus of claim 17, further comprising at least one electroniccompass, and wherein the at least one processor is configured todetermine the heading information from the at least one electroniccompass.
 19. The marking apparatus of claim 16, further comprising atleast one global positioning system (GPS) receiver, and wherein the atleast one processor is configured to determine the heading informationusing information from the at least one GPS receiver.
 20. The markingapparatus of claim 1, wherein the at least one processor is configuredto at least one of translate, rotate and zoom the digital image.
 21. Themarking apparatus of claim 20, wherein the at least one processor isconfigured to at least one of translate, rotate and zoom the digitalimage in response to user input indicating a desired orientation or zoomof the digital image.
 22. The marking apparatus of claim 1, wherein thedigital image is a first digital image, and wherein the at least oneprocessor is configured to cause the first digital image to be replacedon the display device with a second digital image that is in response toa change in the geographic location of the marking apparatus.
 23. Amethod for displaying information on a marking wand having a housing, amarking dispenser holder coupled to the housing to hold a replaceablemarking material, an actuator that, when actuated, causes dispensing ofthe marking material, a display device coupled to the housing, at leastone sensor, coupled to the housing, to output geographic informationindicative of a geographic location of the marking apparatus; at leastone memory, and at least one processor, coupled to the display deviceand the at least one memory, the method comprising: generating via theat least one processor, a digital image based at least in part on firstdigital image data selected by the at least one processor, wherein: theat least one processor is configured to select the first digital imagedata based, at least in part, on: at least one of facilities map data,survey map data, land survey data, photographic image data,constructions drawings, and engineering drawings; and the geographicinformation output by the at least one sensor and indicative of thegeographic location of the marking apparatus; displaying on the displaydevice coupled to the housing of the marking wand the digital image thatis generated by the at least one processor; and overlaying on thedisplayed digital image, based at least in part on the geographiclocation of the marking apparatus, at least one electronic markingrepresenting a detected absence of the underground facility.
 24. Themethod of claim 23, further comprising: obtaining at least a portionfirst digital image data from a remote device.
 25. The method of claim24, further comprising: storing the at least the portion of the firstdigital image data in the at least one memory.
 26. The method of claim24, wherein the at least the portion of the first digital image datacomprises at least one map image.
 27. The method of claim 23, whereinthe at least one processor is configured to generate the digital imagebased on at least a portion of first digital image data.
 28. The methodof claim 23, wherein the at least one memory stores digital image dataincluding the first digital image data and wherein the method furthercomprises: selecting the first digital image data in response to a userinput.
 29. The method of claim 23, wherein the at least one memorystores digital image data including the first digital image data andwherein the method further comprises: selecting the first digital imagedata in response to information provided by the at least one sensor. 30.The method of claim 23, wherein the at least one memory stores digitalimage data including the first digital image data and wherein methodfurther comprises: selecting the first digital image data in response toa user input and information provided by the at least one sensor. 31.The method of claim 29, wherein the at least one sensor comprises aglobal position system (GPS) receiver that is coupled to the housing,and wherein the information provided by the at least one sensorcomprises information indicative of the geographic location of themarking apparatus.
 32. The method of claim 31, wherein the at least onesensor comprises an electronic compass, and wherein the informationprovided by the at least one sensor comprises information indicative ofa heading of the marking apparatus, and wherein the method furthercomprises: selecting the first digital image data based at least in parton the heading of the marking apparatus.
 33. The method of claim 29,wherein the marking wand comprises a marking material sensing deviceconfigured to detect a color of the marking material in the markingdispenser holder, and wherein the information provided by the markingmaterial sensing device comprises information indicative of the color ofthe marking material in the marking dispenser holder.
 34. The method ofclaim 23, wherein the method further comprises: selecting the firstdigital image data based, at least in part, on information obtained froma ticket associated with a locate operation.
 35. The method of claim 34,wherein the information obtained from the ticket comprises an address atwhich the locate operation is requested to be performed.
 36. The methodof claim 35, wherein the information obtained from the ticket comprisesat least one member code indicative of a facility type to be markedduring performance of the locate operation.
 37. The method of claim 35,wherein the information obtained from the ticket comprises informationidentifying an entity that requested performance of the locateoperation.
 38. The method of claim 23, further comprising: selecting thefirst digital image data based, at least in part, on a virtual whiteline image that indicates a location at which excavation is planned. 39.The method of claim 23, wherein the first digital image data comprisesfirst facilities map data, wherein the at least one memory storesfacilities map data including the first facilities map data, and whereinthe method further comprises: selecting the first facilities map datafrom the facilities map data stored in the at least one memory.
 40. Themethod of claim 23, further comprising: selecting an orientation atwhich to display, on the display device, the digital image, based atleast in part on heading information indicative of a direction in whichthe marking apparatus is moving.
 41. The method of claim 40, wherein themarking apparatus further comprises at least one electronic compass, andwherein the method further comprises: determining the headinginformation from the at least one electronic compass.
 42. The method ofclaim 40, wherein the marking apparatus further comprises at least oneglobal positioning system (GPS) receiver, and wherein the method furthercomprises: determining the heading information using information fromthe at least one GPS receiver.
 43. The method of claim 23, furthercomprising: translating, rotating or zooming the digital image.
 44. Themethod of claim 43, wherein the act of translating, rotating or zoomingthe digital image is performed in response to user input indicating adesired orientation or zoom of the digital image.
 45. The method ofclaim 23, wherein the digital image is a first digital image, andwherein the method further comprises: in response to a change in thegeographic location of the marking apparatus, replacing the firstdigital image on the display device with a second digital image that isgenerated from second digital image data.
 46. The method of claim 45,wherein the second digital image data comprises information not includedin the first digital image data.
 47. At least one computer-readablestorage medium encoded with instructions that, when executed on at leastone processor in a marking apparatus having a housing, a markingdispenser holder coupled to the housing to hold a replaceable markingmaterial, an actuator that, when actuated, causes dispensing of themarking material, a display device coupled to the at least one processorand the housing, at least one sensor, coupled to the housing, to outputgeographic information indicative of a geographic location of themarking apparatus; and at least one memory coupled to the at least oneprocessor, causes the at least one processor to perform a methodcomprising: generating via the at least one processor, a digital imagebased at least in part on first digital image data selected by the atleast one processor, wherein the at least one processor is configured toselect the first digital image data based, at least in part, on: atleast one of facilities map data, survey map data, land survey data,photographic image data, constructions drawings, and engineeringdrawings; and the geographic information output by the at least onesensor and indicative of the geographic location of the markingapparatus; displaying on the display device coupled to the housing ofthe marking apparatus the digital image that is generated by the atleast one processor; and overlaying on the displayed digital image,based at least in part on the geographic location of the markingapparatus, at least one electronic marking representing a detectedabsence of the underground facility.